Would it not be trivial to spray a can of air upside-down at the epoxy for 30 secs and scrape it out with a screwdriver or craft knife? Paint thinner takes too long and a heat gun isn't exactly mobile (also sticky, eck).
Done correctly, seals aren't tamper-proof but tamper-evident. A little bit of glue isn't going to stop someone determined to steal from my hypothetical bank, but at least I'll know about it.
