Been wanting to follow up and post my "fix" done a while ago that seems to be holding up well for the time being.
Here's the broken mounting point and tapped insert.
FYI the wing is made of ABS plastic so couldn't weld a stronger repair if it were metal.
Mixed and packed the hole with JB Weld "Steel" Epoxy to approximately the same height, then used the bracket to generally line up the hole for drilling. The empty void inside the wing meant I had to use about 3/4 of the epoxy stick. Once cured, had to be careful to choose a drill bit smaller than the supplied Boomba screw or it won't bite when screwed in.
The supplied Boomba rubber washer vs the thicker rubber washer w 8mm hole I used as a shock/vibration absorber and water seal. I replaced all the existing, paper-thin washers with these thicker ones.
Final fixed bracket on the left, thicker washers now under all the other brackets too.
I torqued the screws in to what I felt to be appropriate, reinstalled the wing and it's been holding up well. The thicker rubber washers have helped reduce the high-frequency vibration of the wing when the trunk opens and closes (the main reason I believe the risers contributed to fatigue failure in the first place). If it breaks again, wouldn't be hard to drill out the old epoxy, refill, and tap it again. I get to keep the existing wing, the oh-so-controversial styling
, and get back to driving the damn thing!
Hopefully this post helps others who've had wings break from use of risers.