Gerry does indeed sound like a guardian angel.   Hope things work out well for you and Chynna.
I remember having to make that hard decision for my dog George.  But our vet flat out told us that whatever we tried to help him wouldn't relieve his pain and may or may not extend his life.  
I feel for anybody who has to make that decision. 
And don't feel bad about not paying him back Acadia.   Who knows?  Maybe somebody helped him with something in the past and told him to pay it forward.  Now he can.