I have not found a specific demand that immersion in water had to be the sole method of baptism.
Had the KJV translators not chickened out and lacked the courage to translate rather than transliterate the word Baptidzo there wouldn't be a problem today.
Let's see what would have happened if the translators had the gumption to translate Baptidzo.
Matthew 3:6 And were immersed of him in Jordan, confessing their sins.
Matthew 3:13 Then cometh Jesus from Galilee to Jordan unto John, to be immersed of him.
Matthew 3:14 But John forbad him, saying, I have need to be immersed of thee, and comest thou to me?
Matthew 3:16 And Jesus, when he was immersed, went up straightway out of the water: and, lo, the heavens were opened unto him, and he saw the Spirit of God descending like a dove, and lighting upon him:
Matthew 20:22 But Jesus answered and said, Ye know not what ye ask. Are ye able to drink of the cup that I shall drink of, and to be immersed with the immersion that I am immersed with? They say unto him, We are able.
Matthew 20:23 And he saith unto them, Ye shall drink indeed of my cup, and be immersed with the immersion that I am immersed with: but to sit on my right hand, and on my left, is not mine to give, but it shall be given to them for whom it is prepared of my Father.
Mark 1:5 And there went out unto him all the land of Judaea, and they of Jerusalem, and were all immersed of him in the river of Jordan, confessing their sins.
Mark 1:8 I indeed have immersed you in water: but he shall immerse you in the Holy Ghost.
Mark 1:9 And it came to pass in those days, that Jesus came from Nazareth of Galilee, and was immersed of John in Jordan.
Mark 10:38 But Jesus said unto them, Ye know not what ye ask: can ye drink of the cup that I drink of? and be immersed with the immersion that I am immersed with?
Mark 10:39 And they said unto him, We can. And Jesus said unto them, Ye shall indeed drink of the cup that I drink of; and with the immersion that I am immersed withal shall ye be immersed:
Mark 16:16 He that believeth and is immersed shall be saved; but he that believeth not shall be damned.
Luke 3:7 Then said he to the multitude that came forth to be immersed of him, O generation of vipers, who hath warned you to flee from the wrath to come?
Luke 3:12 Then came also publicans to be immersed, and said unto him, Master, what shall we do?
Luke 3:21 Now when all the people were immersed, it came to pass, that Jesus also being immersed, and praying, the heaven was opened,
Luke 7:29 And all the people that heard him, and the publicans, justified God, being immersed with the immersion of John.
Luke 7:30 But the Pharisees and lawyers rejected the counsel of God against themselves, being not immersed of him.
Luke 12:50 But I have a immersion to be immersed with; and how am I straitened till it be accomplished!
John 3:22 After these things came Jesus and his disciples into the land of Judaea; and there he tarried with them, and immersed.
John 3:23 And John also was immersing in Aenon near to Salim, because there was much water there: and they came, and were immersed.
John 4:1 When therefore the Lord knew how the Pharisees had heard that Jesus made and immersed more disciples than John,
John 4:2 (Though Jesus himself immersed not, but his disciples,)
John 10:40 And went away again beyond Jordan into the place where John at first immersed; and there he abode.
Acts 1:5 For John truly immersed in water; but ye shall be immersed in the Holy Ghost not many days hence.
Acts 2:38 Then Peter said unto them, Repent, and be immersed every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.
Acts 2:41 Then they that gladly received his word were immersed: and the same day there were added unto them about three thousand souls.
Acts 8:12 But when they believed Philip preaching the things concerning the kingdom of God, and the name of Jesus Christ, they were immersed, both men and women.
Acts 8:13 Then Simon himself believed also: and when he was immersed, he continued with Philip, and wondered, beholding the miracles and signs which were done.
Acts 8:16 (For as yet he was fallen upon none of them: only they were immersed in the name of the Lord Jesus.)
Acts 8:36 And as they went on their way, they came unto a certain water: and the eunuch said, See, here is water; what doth hinder me to be immersed?
Acts 8:38 And he commanded the chariot to stand still: and they went down both into the water, both Philip and the eunuch; and he immersed him.
Acts 9:18 And immediately there fell from his eyes as it had been scales: and he received sight forthwith, and arose, and was immersed.
Acts 10:47 Can any man forbid water, that these should not be immersed, which have received the Holy Ghost as well as we?
Acts 10:48 And he commanded them to be immersed in the name of the Lord. Then prayed they him to tarry certain days.
Acts 11:16 Then remembered I the word of the Lord, how that he said, John indeed immersed with water; but ye shall be immersed with the Holy Ghost.
Acts 16:15 And when she was immersed, and her household, she besought us, saying, If ye have judged me to be faithful to the Lord, come into my house, and abide there. And she constrained us.
Acts 16:33 And he took them the same hour of the night, and washed their stripes; and was immersed, he and all his, straightway.
Acts 18:8 And Crispus, the chief ruler of the synagogue, believed on the Lord with all his house; and many of the Corinthians hearing believed, and were immersed.
Acts 19:3 And he said unto them, Unto what then were ye immersed? And they said, Unto John's immersion.
Acts 19:4 Then said Paul, John verily immersed with the immersion of repentance, saying unto the people, that they should believe on him which should come after him, that is, on Christ Jesus.
Acts 19:5 When they heard this, they were immersed in the name of the Lord Jesus.
Acts 22:16 And now why tarriest thou? arise, and be immersed, and wash away thy sins, calling on the name of the Lord.
Romans 6:3 Know ye not, that so many of us as were immersed into Jesus Christ were immersed into his death?
1 Corinthians 1:13 Is Christ divided? was Paul crucified for you? or were ye immersed in the name of Paul?
1 Corinthians 1:14 I thank God that I immersed none of you, but Crispus and Gaius;
1 Corinthians 1:15 Lest any should say that I had immersed in mine own name.
1 Corinthians 1:16 And I immersed also the household of Stephanas: besides, I know not whether I immersed any other.
1 Corinthians 10:2 And were all immersed unto Moses in the cloud and in the sea;
1 Corinthians 12:13 For by one Spirit are we all immersed into one body, whether we be Jews or Gentiles, whether we be bond or free; and have been all made to drink into one Spirit.
1 Corinthians 15:29 Else what shall they do which are immersed for the dead, if the dead rise not at all? why are they then immersed for the dead?
Galatians 3:27 For as many of you as have been immersed into Christ have put on Christ.