IMHO the vast majority of RC's are not saved, .
Your admission here destroys your whole argument. The fact that the "vast majority" are not saved does not mean NONE are saved and they are part of your universal invisible church and their doctrine is Catholic Doctrine. There are saved in the SDA, pentecostal, Methodist, Lutheran, etc. This destroys your whole argument about unity in essentials. The facts simply do not support your position at all.