[mathilda]

are these dogs intact?
It could be that Drifter notices that Ragnar is becoming an adult and doesn't want another male close to him. until recently he was seen as puppy so Drifter was okay with him.
same sex aggression is pretty common with dogs.

 

[mathilda]

before rehoming, I'd neuter Drifter and observe if his behaviour changes.
generally, I believe that if an older dog has lived longer inside a family it is better to rehome the younger dog. the younger the dog, the more likely they'll be adopted in a shelter. People will almost always chose the younger dog, even if the older dog fits better in their life.
If you must rehome one, I'd probably think of rehoming Ragnar.

 

[mathilda]

Harsh? The OP asked twice about posting a gofundme link. I'm not going to believe every request for money is actually toward a worthy cause. People scam other people all the time on those type of sites. Some are surely legit, but how is the average bleeding heart supposed to weed out the legit from the scammers? The reason this forum and most don't allow this type of link is because they don't want to seem to be endorsing the pleas for money that may or may not be legit.

Me, I'd be working two or three jobs, selling off my stuff and borrowing from friends and family before I'd ask total strangers to send me money.

The book I suggested is actually one I'd suggest to anyone having this problem and especially if they couldn't afford a trainer.

What I'm asking myself is, if you can't afford a trainer for one of your dogs and the dog shows interspecies aggression, Why'd you get a second one?
especially one of the same gender.
and if you can't afford a trainer...can you afford getting two dogs spayed?
with the dogs getting older, they probably need more medical attention, so there'll me more costs in the future. You sure you can do that?