Yes it will be fine... Its always better to use epoxy over bare metal, on a spot that small I would not bat an eye.. I dont hardly think you are going to lose any adhesion over that spot.. The benefit over the 2k with epoxy is corrosion protection.. Now if you have something chip there it would be better with epoxy on it, but again, I dont think this is really going to be an issue..
People used to strip cars to bare metal and cover them with 2k years ago all day long.. Epoxy would have been better, then 2k, Im just giving you a reference point is all
If your doing a resto, then you can spot those area's in if you feel the need with 1 coat of epoxy, wait an hour and then apply 2k.. Most will tell you this is the best option, and it is!!! Im simply telling you if you didnt want to, the paint wouldnt fall off your ride or anything