Heheh I'm not lying. My 2 characters and my friends character took minigun blueprint as reward.
I have 2 minigun plans in chest, and 1 was used by my friend to create minigun in fixboy.
Two times I gave 800 caps for motivator and 700 caps once.
Maybe it's something about way I made this quest?
I talk to scientist, check robot, buy motivator in hub, next use motivator on robot, fix it, talk to scientist and take minigun blueprint.
All characters had 1LUCK, and all had different skills.