Hi @SusanLogan
I would echo the things @Peonie19 and @shafofo have suggested. And use that guide! It’s great!
I’m a homeowner and have a cat with things “above the norm”. I 
percent get the need to want to identify any /all issues, so a sitter is not surprised by them. However, it is a balancing act to put just enough detail, so a sitter can make an informed decision about whether they are a match for you, but not so much that they stop reading. 
You and your husband seem like a such very nice couple, and Logan looks like a dear large loving dog. I think it’s really important and honest that you have highlighted some of the challenges you and your lovely doggy have experienced in terms of his potential reactivity. It may mean while you get fewer sitters interested in dealing with a more reactive dog, the ones who contact you understand what’s needed.
A few things:
I honestly don’t see any major “red flags”, other than the length and detail, and some inconsistencies. It may not just be the best sit for some sitters. That in and of itself is not a red flag.
Your listing needs an edit, for content, flow, and punctuation for readability. I am no Shakespeare; I tried to take your listing and cut and paste it into a Word document to do a trial edit, but I was not able to do so. It may help to get a family member or someone else just read through it for editing purposes. If you are familiar with ChatGPT, it could help with that too. @Shafofo made great suggestions.
I also wondered if a little too much is in some sections that can be chopped out, and otherwise go in your welcome guide. I think @Peonie19 also suggested this.
Consider taking out the extra details about your back injury from the listing. You can share that in a video chat. If relevant. Simplify. Use bullet points. Type it out first in a word document.
You put quite a bit about your training techniques with lovely Logan; I wasn’t clear if you were doing so just for information purposes, or if you were expecting the sitter to engage in specific training sessions. I think a lot of that can be removed from the listing and put in the welcome guide with a statement saying that he has had recall training and can follow commands.
Highlight, ( above and beyond the merits of hanging out with Logan, what your home and local area have to offer (day trips, restaurants, hikes, parks). I did eventually DID find that in your listing, but in your edit, I would put a sentence of what would attract somebody to come to do your sit above and beyond Logan himself. How much time in a day or week would the sitter have to explore- can your dog be left alone for a time- and in that time- what cool things are there to explore. Highlight that you allow a sitter to use your car.
You definitely don’t need to make your home a show home, but wouldn’t show the bedrooms or spaces that your sitter can’t use? Edit your home space photos to showcase the rooms/spaces your sitter can use. Spotlessly made up comfy bed, spotless uncluttered kitchen and their bathroom. For example, you indicate in the amenities that a king size bed is available, but in the body of the listing text you indicate that a trundle bed is available for the sitter. Just be consistent. Only put in the listing what is available to the sitter. If the sitter can’t use your bedroom and your king bed, don’t make it available and don’t show pictures of it . Make the bed that the sitter will use comfortable; bed and bedding look well made, clean, sharp and inviting. Clear all extra clutter ( the normal clutter many of us have😉) from kitchen for the photos.
As you have identified a security camera, I have found some sitters like to know where it is located when applying for the sit. In exchange for what you will edit, put a line about this in to reassure sitters you won’t be monitoring them.
Some sitters will self select out of a sit that has a cameras (even one that’s permitted, externally). That’s ok- you want your sit to be a match for YOU and your SITTER. For example, I have a doorbell ring camera, and in my listing, I identify that so they can ask questions about it. Presumably, you’ve some sort of exterior camera as per the TrustedHousesitters terms and conditions as of course, no inside monitoring devices are permitted.
Good luck, I’m sure you’ll find a trusted sitter for Logan soon. As he’s a pretty special pooch, plan far ahead, be flexible.
Responsibilities section still needs slimming a lot in that second half (or it sounds as if you & Logan are high maintenance which you’re not), you could either bullet point it or halve it to the WG for later. Tiny thing - if you swap “with” for “&” in your title then the whole word of “setter” will then show as sitters scroll. You can also now pause & relist your dates and you should then show as “new” and not “low applications” which will help too. 