I am Also having this issue (still), just to vouch. Cant seem to find a pattern for when they randomly unlock.
As you guys know, I often wipe save. Obligatory disclaimer that I am not telling you should wipe save because apparently someone else wiping affects you.
Anyway, with that aside, it has opened me up to a bug a lot of the "veterans" (cringe) won't be able to observe due to having most if not all engineers unlocked already, and I suspect, haven't heard of the bug.
Basically, and I imagine this has been happening to a lot of, if not all the new players around right now, engineers are unlocking for players randomly, without even beginning to touch upon their unlock requirements. They aren't just being invited to the bases. The menu is showing them as having donated whatever has to be given to the Engineer upon arrival already, even though they have never been to their bases. (For example the 500k you give to The Dweller)
Needless to say this is a huge exploit. And we don't like exploits here do we?
I'd like to show you one of the bugs that is a real problem for the game right now. Engineers unlocking randomly and for "free"
South Carolina? What's SC? Why do people in the ED community throw around acronyms like they work for NASA?
Super-cruise. It's been around for quite some time, that one
There are quite a few initialisations in this game and we do tend to throw them about a bit too much, I agree.