It clearly has the freedom so I should be able to make a point coincident with the line as I prove in the demo video. Why doesn't it mate? And I tried making the two lines colinear, didn't work either as you can see in the demo. No good, it requires me to break other mates.
Video#1 :
That's another issue on top of that. This thing behaves rather oddly, it's obvious coincident to the PCB (green) but I don't see it on the mates list. That's video #2
Video#2:
There are some copyrights issue with this file and it's a big assembly so I can't really upload it however I did attach the electronic connector that I'm working with. The other part (green) is just a flat part with a square hole
Problem solved, I had aligned it against a plane instead of against a center line