Based on the Reddit post it sounds like it should be relatively simple to set the announcer from any announcer you own in arcade and custom campaigns. https://www.reddit.com/r/starcraft/comments/5899l5/do_the_new_paid_announcer_work_in_arcade_games/
I poked around a bit but couldn’t figure out where to go to change the CGame_EnableRewardVoicePacks value, and throwing that term into Google on brought up the page above. If anyone could point me in the right direction that would be great.
Likewise, is there a way to use the SC1 announcers when playing custom single player maps in SC1? Does it work by default or do you have to mess with it?
I asked Blizzard support about both of these but getting more money out of me for DLC than I spent on both games (on sale) doesn’t warrant a response, apparently.