Actually heat is one of the recommended ways to get rid of bubbles in epoxy:
(if you convert the recommended temps in that to F it is about 95-104)
There is a boat builder in GA that has a special heated room where he does his epoxy work.
My own experience is that epoxy gets very tricky at high temps, although it may not bubble as much as at lower temps. I think you're right that the air bubble here is just air trapped in the hole.
The builder in Georgia that you refer to, Robb White, would heat up his boat barn with his wood stove and get it REAL hot in there. But he did not apply epoxy until he had doused the stove and allowed temps to begin falling. In this way, the hot wood (Rob preferred Tulip Poplar), now cooling, would soak up the epoxy like a sponge, making for a nice, even, bubble-free, clear finish.
I hate to deliver bad news via internet, but Robb passed away in May of '06, during an operation to clear a blood clot. I expect his son Wes still uses the same techniques, but he's not a full-time boat builder to my knowledge.
Robb was an amazing raconteur. If you haven't already read it, pick up a copy of How to Build a Tin Canoe
. Or find yourself some back issues of Messing About in Boats
. Many good nuggets in there for the would-be builder.