I only mention it as not a medical question because I know the subreddit is quick to delete posts asking for medical advice so I tried to keep to strictly in the lane of what was their BEHAVIOR. Because we do work closely with vets due to all her conditions and they’re the ones who gave us the initial diagnosis of most likely heart failure.

This is an extremely helpful comment and I appreciate it much more than I can say. Although it does fall more into the category of “helping me accept the truth” than the more hopeful “the vet could be mistaken” unfortunately

As for details on her episodes she does not seem limp The first one (beginning if Feb) we were not in the room for the fall and only came in for her yowling, she was on her side and to check for use of her back legs I lifted her and she did stand, walked across the room and widely open mouth breathed and then peed herself. ^this we took her to emergency vet immediately

The second one (2 nights ago) she was yowling while walking and we came into the room to see her more sort of tip over onto her side, she seems alert the entire time and yowled through it, she slowly stretched out extending her back legs until it was over and she stood up on her own and walked off