I don't have any experience with medicine or special requests, but I LOVE best friends pet care at disney. We rescued a dog who is VERY shy and needy because she stays with me all day as I work from home.
Her first boarding experienced I booked an indoor/outdoor option. Once we got there though they had me down for the indoor option. I wasn't happy but once they explained she still had access to a little outside patio and got two potty walks instead of one (only one potty walk with indoor/outdoor) I was ok. They were book solid as it was around Thanksgiving last year, so I didn't have an option.
I booked her some extras like ice cream and doggy daycamp, but I let them know to please note that she has no experience with playing with other dogs, so if she is not happy please exchange it for a walk or something. During our trip I received an email with her picture letting us know she was doing great!
The lady was kind enough to let us take her back there and I wanted to actually see what the accomodations were. With Tucker being so shy and timid I wasn't too excited with the set up but I knew she would be fine. It was a long hallway type with dogs on both sides and it was SOOOO loud with them all barking. I was assured they are not always like that though. (I have heard others asking to take their own dog back and were told they could not... it was not busy when I was allowed to go back. Not sure if the person or timing makes a difference there)
A couple things I didn't care for was that she could only have a couple toys. Our dog loves her toys and really plays with all of them so I brough about 4 of her favorites. I also brought her bed and her blanket and explained not to lay the blanket in the bed as it was another option for her to lay on... While the bedding was fine, she couldn't have all her toys. I imagine I was not the first crazy dog owner in there.
I gave them her chewy bone, food, and treats. In the bag of food I had a scoop as her food instructions was one scoop a day. The scoop did not make it home somehow.

I didn't notice until we got home.
Another thing I didn't care for is the sticker collars.They remove their collars and put their name on a white paper collar that is sticky on the end to put it on them. Not sure how to word that better.. hope you know what I mean. When we got her home we had to cut her fur to get it off because her fur was all stuck in the paper collar where it was sticky. No huge deal, but next time I will ask to put it on myself!
Please keep in mind I am the person that loves my dog like my child as I have none. I bawled my eyes out when we boarded her for the first time.
With your dog needing to go to the bathroom a lot, I don't think they will have trouble with that since every option (I believe) gives the dogs access to a little outdoor potty area. Even with a day trip you can get day rates for boarding or see what the potty options are for doggy daycamp.
We have also had Tucker groomed there and had a great experience. We had her glands expressed, nails trimmed, groomed, and bathed for a fraction of what my vet charges. Also I met with the lady who would be taking care of her and she was so kind. Tucker smelled awesome and was very happy when we picked her up!
Everytime she has stayed there they proved little report cards at the end too letting you know how they were for boarding, daycare, and grooming depending upon what you choose. She is going back this September, but I have a villa reserved so she won't have to be around all the dogs. It also gives them a TV which I always leave on for her at home, so I hope it makes her feel more comfy.
If you are a resort guest or an AP holder don't forget to ask about discounts. I have an AP and get great rates!
Their web site has a ton of info
http://wdw.bestfriendspetcare.com/
Sorry for such a long post. I know I had trouble finding info before I took my dog there so I wanted to be thorough!

Have fun!