I wouldn't even properly describe Galloway as injury prone even though he's had these two big ones with his Achilles. It's not like Delaney which is knee one time, hamstring the next, then groin, then back etc. If Galloway comes back ok from this one I would t be too worried or expectant of him breaking down again.
Delaney is about 5th choice backrower now, he still plays well when fit and around 15 games for a 5th choice isn't the end of the world that we need to get rid now when his contract is up at the end of this season anyway.
Whilst it may not be to everyone's agreement I think the club see something in sticking with guys who have helped them be successful and not just ditch them at the first sign.