If one has declined, you might want to decline their application so that it shows as only one applicant if you are still considering the other applicant. I know some forum members fear the “low application” label. As a sitter, I don’t avoid them. In fact, if I like the listing, it’s a bit of a relief to know there’s not much competition. When sitters are fairly new to the site, which doesn’t mean they’re not experienced with pets, they are encouraged to apply for “low application” listings. I have done 38 sits now, all 5* and, all things being equal, I still prefer to apply for sits which are not in very high demand. I can take my time writing the application without fearing it’s going to go into reviewing mode in a minute.
I don’t see anything off putting in your listing, I have never looked after especial needs cats but I would like to and the description sounds perfectly manageable for a solo sitter. However, I would not apply because you only mention couples.
IF you are open to solo sitters, I suggest adding a sentence after specifying “Good for couple…” (a solo experieced sitter would be great too) or (the right solo traveler with experience would be great too) or something lie that… make the solo sitter feel that they should apply if they are interested. The current statement seems pretty closed off to solo travelers. Make it more attractive for the very large pool of solos out there.
I think you should really think about whether the sit requires two people or not before opening it to solos. Reading the listing it sounds like it would be fine for solos, but some of your statements seem to imply the sit requirements are more involved that what the listing seems to indicate. Since you are looking for a good fit, make sure your listing is very clear on the work involved and if it does require a couple then stick with that.
I would have loved to come and care for your very special cats, but unfortunately I’m fully booked up for this year. Are you aware that you can be a little more proactive and search for a sitter, then send them a request? As someone who loves caring for elderly pets, I can think of many ways i, as a solo sitter with car, could manage to have a great time WITH your cats, so I’m sure there must be others out there. There are also many ways in which you can make life easier for a sitter too, regarding little ‘accidents’. If you are on FB, have a look for reels done by Cappy the disabled cat for ideas.