I got an Idea. Maybe when you join a guild there is something  created  at random in your account like a flag.  Has anyone tried leaving and returning  to your guild  to see if eligibility  changes?
I M not a programmer but I think developers  know the problem however  the cause is  also a feature in their code and developers  do not know how to keep the feature and not have it affect  the gifting special. Or they have to do some coding for the gifting module.
Regardless,  communication AKA customer support is up there  with product quality  when it comes  to software