I have do direct knowledge, but what I've read comes down as follows.

"Generally
it is easier for a pet to adapt to a hind leg amputation than a
forelimb amputation, because most dogs bear more weight on their front
legs than their rear legs,"

I've always been suspicious of this, but it seems that most dogs adapt quite well - whether front or rear.

I get a magazine from Best Friends, which is a pet sanctuary. This month there's an article in it about a dog which had 2 legs amputated; a rear leg first, then a front leg. (He had been a stray, found a family and then became a stray again.) he seems to get around on his 2 (I do believe the 2 remaining legs are on opposing sides). They mention that he has made some adaptations, if he's standing still he either has to lean against something or someone or else sit down, and when he pees, he presses his nose to the ground to steady himself.

I've actually known several tripods with front leg amputations, they seem to function just fine.

Aw, that poor thing! I've seen lots of 3 legged dogs but never a 2 legged one!

I my own self would get an opinion from at least one more veterinarian.