Good question
I decided to google
https://www.gcfa.com/
The first thing I noticed when looking into this site they look to rehouse.
30 years experience over 8,000 ferrets. So if they're to be believed they definitely have some experience.
Also a 501c3.
I can't find any lists about their turnover but it shows currently they have 98 ferrets in the census currently with at least 6 listed as adoptable.
There also appears to be more you can ask about in a contact.
No real info about their care for ferrets that have terminal illnesses though.