DKViner BooDestroyer has pointed me to an artile about a developer (who would later to go on to work with other Nintendo properties on the CD-i) taling about his brief experience working on a Donkey Kong arcade game for Sega back in the early 80s!
Seems the big ape was going to be a parking attendant of some sort. Weird.
This also raises the question of whether Congo Bongo started life as a legit DK game prior to Sega's ownership issues causing the deal to fall through.