No, but do i think that Epoxy is strong enough to do the job, Maybe. That's why I am polling. Also, while the mounts are important, I feel that the weakest part in the system is where the two m4/m5 bolts hold the caliper to the mounts. I think as long as i can match/exceed this required force, then it would work

As for the photo of mount adapter that I attached, that was the first thing I thought of that would give a flat surface to bond to the fork, and provide the sideways mounts for my Shimano calipers. If i have to fabricate the thing myself, I think i would try to create something that would clamp over the fork, then i could reinforce with epoxy.