Palpatine clearly says “the life force of your bond… a dyad in the Force” so it’s not something they were born with, but a connection that grows within them. So it doesn’t contradict Rey being a nobody, if anything it would strenghten that point if a nobody could develop such strong connection in the Force. And I also don’t see Snoke bridging their minds as a contradiction, but rather a step towards such a strong connection developing. Maybe it would help if Kylo said “What Palpatine doesn’t know is we’ve become a dyad in the Force, two that are one”.

As for the “every voice” line, I get that it doesn’t have to be litteral, that you can read it as hyperbole from Palpatine’s side. But I’m looking at it from the angle of the average viewer who either hasn’t seen the movie, or just hasn’t been dissecting it for months, and hasn’t read the expanded material. Palpatine says he has been every voice he has ever heard, while mimicking Snoke’s voice, it’s hard to read that as anything other than literal, that when Snoke talked it was actually Palpatine talking. If the line was only delivered in Palpatine’s voice it would be fine, as he could just be refering to the fact that he created Snoke, and Snoke turned Ben and became his Master. But the fact they make him speak in Snoke’s voice just makes it all confusing, when I saw the film in theaters I certainly thought they were saying Snoke was Palpatine all along.