Put my mind at ease please

I know no one can tell me for certain but I’m spiralling a bit after the update on our chain today… for context we, the people above & below are all ready for exchange this is r.e the flat at the bottom.

• We have been told today that the bottom link buyers ID needs some additional verification, the buyer is currently in China, returning this Saturday, until this is rectified all legal work has ceased, we will of course chase on Monday. They have confirmed they do their mortgage offer and searches have come back -

Surely you cant get a mortgage if your identity isnt verified. Have spoken to our EA and they agree, we are all hoping its an admin error/accident overseeing the forms but we’re 10 weeks in ffs….