Thanks for the good helpful replies, you gave me some good ideas and encouragement….
I was ready to cry yesterday looking at the broken screw.
So many good replies like wind in my sails.

Eventually I used a long piano wire to fish a new blind nut and positioned it instead of the old one, then with another blind nut and a long screw I positioned it and stressed it into position and epoxy around it to close the gap of drilling.

I was always thinking oh god to replace this nut its such a pain…

Anyway I almost finished the airplane, just pushrods and CG.

Thanks alot
Alex