Can the solo loop band be removed so I can slide my medical ID on it?

I'm not sure you will want to do that, but you can slide either or both ends of the Solo Loop off the Apple Watch using the same retention mechanism used by all other Apple Watch bands, locate the ID onto the Solo Loop band, and then slide the band back onto the Apple Watch.

I'd be concerned about chafing or dermatitis or other problems arising.

This also assumes the ID can be fit around the widest part of the Solo Loop.

Here is how to: Change your Apple Watch band - Apple Support — see the section "Change your band". The Solo Loop section below that section describes how to take the watch on or off your wrist, and not how to remove the band itself from the watch.