I vote that you concentrate on Indy and let Dega be. While it is possible to train Dega, I think your time would be better spent making Indy the pure hunter. It is tough enough to train a 2 year old dog that is from a fantastic pedigree, much less deal with the unknowns you've got here. Seems like she functions well as a flusher, be grateful you didn't have to work a lick to bring that out. After you get Indy trained, come back and work on retrieving with Dega. By then, with Indy scooping up every feather that hits the ground, Dega might teach herself due to the competition!
All dogs don't need to be hunters, the tennis ball freaks are quite fun as well. Train her to be a "Dock Dog"!
Course that is just my opinion... Dega isn't my dog
"I'll start spending less time with my dog and more with my wife when she starts fetching ducks for me"