Huh. Disappointing. So basically the fault comes from no grip between insert and glue. Maybe some serrated inserts would work ? But you'd have to redo everything. Or the insert should actually be without threading and used with a bolt+nut
Well seeing as I plan on commuting on this tomorrow I’m gonna try glue for today and see what happens. I’d like to avoid using a bolt if possible but may have to be pragmatic….