Do you buy a Series 8 (GPS+Cell) w/ broken screen - or know of anyone

If you don't want to repair it, your best bet is to unpair it from the phone (this will remove the activation lock) and sell it on a site like eBay; iFixit doesn't buy devices from individuals.

For future reference, AC+ on a Watch is not an option unless you consider it a disposable item! When I got my S8 (semi-permanent Target sale) I couldn't buy it through Target; just Allstate coverage (better kickback, likely). I added it to the watch right after I got it and finished the setup through Apple directly because of the cost of a repair on these things with AC+ vs without (and less headache if I need it since I can just take my watch into a store); if I break my screen and the glass protector does not save it, it's a $99 mistake with AC+. For the S8 without AC+ it's like $299 through Apple. Normally I wait when things get close to September for Watches and iPhones, but I made the exception on the watch because the S8 was still pretty fresh at that time (7 months at the time). If I was shopping now, I'd be waiting a bit because of when the new devices come out.