Hello,
Well this is a somewhat difficult question to answer. Here has been my experience. If you do not have the ability to see a surgeon and have this corrected by them (in my area it would be anywhere from $2000 to $5000. Then I always suggest strict cage rest. No leaving the cage for two weeks. No exceptions. The crate should have a very low bed, low sided litter box and food and water. They should be fed a watered down wet food to keep the stool soft and easy to pass. After two weeks see your vet for a recheck X-ray to see how the pelvis is healing.
Have the cat spayed asap.
If the cat presents with anal tone and deep pain in all four feet I recommend cage rest
The best option is surgery. If you cannot afford it try cage rest. They will be painful for a few day. A fentanyl patch might help or try buprinex. Ask your vet about these.
Let me know how she does
I think it is very kind that you took on the responsibility that your former neighbors didn’t. As far as having them in your house with the rest of your pets, part of that depends on how they all react to each other. Keeping them separate at first would be a good way to introduce them. You may be surprised and they might integrate well into your household and you might end up doing just fine with everyone altogether… but you’ll probably need a new swiffer? In all seriousness, in my opinion with cats especially, they’re so self sufficient in so many ways that having more is usually not a big deal. The only thing I am not a huge fan of is the extra litter boxes – which I have delegated to the kids. Best of luck!!