Quite frankly I would do what is right for you.
They might be good guests , but it was also their own responsibility to research your place in the first place.
I had the same problem ,I had good guests that was booked by their son. He failed to read my description and note that instead of a bed I had 2 mattresses. Naturally this became a problem for them and they left and left a scathing review and even commented how hard it was to have a proper bed and I should make it cheaper.
I was hurt as it wasn't my fault if the son was too lazy to read the full description and reason for the matteresses was I was not sure how long term the place was going to be available for renting out and I had priced it accordingly. So I choose to ignore it.
But I always regretted not having my say, that I felt in saying something honest will leave a bad impression and give them a bad experience. I failed in saying how these good guests ,cancelled after 2 days asked for refund when it was clear in my terms and condition that they weren't entitled to it. So again, they failed to read my description. By not having a say to this guy I felt like I robbed myself of a chance to remind him how to become a better guest by reading and not be a lazy cheap skate for his parents.
On another note, about the cats. I have 2 ,and one of them loves going to the apartment next door to say hi. My airbnb place is just next door but there is a balcony that is connected. My neighbours also have pets ,their cats rarely visit but it happens. I have included this in my description.
I am lucky to say I have guests who don't mind at all and have come around to love the visits they get. Even had an incident where my cat got stuck locked in and had woken them up to tell them to let him out. They found it funny and loved that my cat was so communcative.
But I had annoying annoying, let me emphasis this again, annoying people messaging me about the cat situation. Asking is that my cat to how they like to roam about .I had one lady asking the same question thrice in three different ways. I said, if you don't like cats and this is an issue, please don't book. How hard is it for guests to understand that. Hard apparently for a few.
As much as we love to be good host, you do get the occassionally (can I say it), get idiots.
So be firm, it is your place, you have no control of what your cats go through and that comes part with the terrority.
I have stayed at place with 2 cats and 2 dogs. No problems and if I saw a poo , I know that is my own fault for booking such a place. I would not blame it on the host but of course I would warn them of the mess.
To @Leigh29, your comment is one that annoys me because it is not constructive at all and provides no insight. Your attitude is one that is reflected in the same as the guests I get when they ask the same question about the cat situation.
I get annoyed when people have the responses as you do when it comes to Airbnb. This is such an unique renting platform where we get to experience and to live in homes both real and amazing and that comes with the quirks and differences to your own. So when a home has pets, it has pets. Your comment is suggesting that Karin holds a zoo, was demeaning. She fulfilled her end by being a host, she cleaned it up, she made it clear in her posting she has pets. What comes out of her pets is beyond her control. I have 2 and I clean like crazy but I can not ask my pets to stop shedding their fur or scratching the carpet. If you want to post something. Post something worthwhile a thought. Not this useless empty remark.