Unless you solvent-weld it to a bit of the same plastic (affixed to the metal of the bracket), it’s going to fall off one day. Any glue joint held continually under strain and subjected to repeated cycles of heating and cooling, will be prone to failure.
The stuff they use on the flaps of Priority Mail boxes. Man, that crap is strong and permanent, even if the flaps accidentally touch, BAM! They are welded together. It doesn’t solve your problem, but I just had to put that out there in the “stuff you don’t want to get on your junk” category.
That’s some sort of contact adhesive that is applied to both parts and dried - it then bonds instantly on contact with itself.
However, that doesn’t mean that it will bond effectively to the surfaces you put it on.
A couple of minutes on google found this:
Clamps to hold a non VESA monitor and then attach it to a VESA mount. There you go.
This site seems to have solutions to fit more or less anything:
Nope. Mine is a Samsung C27F591FDE. I’m just going to use Goop, I’m familiar with it and know from experience it’s pretty tough, especially for something only 10lbs. I couldn’t find any reliable information for other adhesives that gave me any better confidence than Goop.