So I'm in a realtime game where I have lost and surrendered, but the enemy team won't kill me or accept my surrender. They are waiting for me to time out so they can boot me. Is this reportable or just bad manners?

bad manners

or auto boot will prevent(?) this

auto-boot, is still a boot..
key is to join games with no accept on surrender..

post game and spread the blacklist around

If you have time to waste......wait every turn and make move 2 sec before time out. Very often this make them accept.

If you dont have time.....let them boot you, post link in forum and add them to black list. There is not many players like that....so your boot rate will not be big because of this.

they must have been very annoyed with you to do that or just trolls

Maybe they were noob, and didn't know how to accept surrender.

Or, it might be ffa, and it's strategic to NOT accept surrender.

aqua he said enemy team so it is team war