2-part epoxy won't really do much, all you're doing is gluing the screw to the wood. When you get a pull-out 99% of the time the screws are covered in little pieces of your core anyway, they just rip the wood straight out.
If you don't want rip-outs then the key is to use a larger, coarser thread into the ski, like a brass threaded insert where you drill the hole out larger, screw the insert in then use machine screws (which damn near never pull out because it's metal on metal) to increase contact area.
Or, as mentioned, if you want the ultimate in never-ever-ever-come-out then you drill right through the ski with a larger bit, cut pieces out of the base, insert T-nuts with epoxy from the bottom of the ski, smash them in, then patch the base. If you ever managed to pull one of them out you would have to make the core pretty much splinter first.
