If I ever find creepy-crawlies in my Pu-erh, I'll probably do the same
thing. I'd stack all the boxes in a small closet, put in a few pounds of
dry ice, and tape the door shut for a week or two. Dry ice is readily
available in most urban areas, cheap, leaves no residue, and (IMO) is
very unlikely to induce any changes in the tea itself. On the other
hand, CO2 ruins coffee (why European bags have a vent), so I'd probably
test it first.

-DM

Funny thing is that some people believe this to be good and keep such
bug-eaten pu as a prized part of their stash. Look up the bug poop
pu'er threads we've had here in the past.