Will my guarantor be ok if they were accepted for FLM quick?

FLM and FLM quick don't have the same criteria - your guarantor doesn't have to be a homeowner for FLM Quick but they DO for FLM, so it's never guaranteed that they'll be accepted just because they have been for FLM Quick.

They have to have a good credit history for both though so if they pass the credit check for a FLM Quick then that would be a good sign.