My silver bullet needs a vent hole STAT. Will AltSmoke put one in it?

If you stack two batteries in it you'll need more than that - three milled slots are needed. But for single battery use, with a sensible battery, some holes will be fine.

A single battery mod is unlikely to blow unless you are really unlucky or do something stupid (we haven't heard of a 1-cell mod blowing yet). If it did, be aware that gas vent holes are a warning not a protection. You see and hear the gas venting, and maybe your hand gets burnt, so you drop it. Then it goes bang. A few holes are nowhere near enough to vent the gas produced.

But anyway this is not a concern using 1 batt. If you are stacking batteries in there, then get 3 slots milled in the body, 50mm x 4mm. Stacking batts in the SB is against the maker's recommendation for a reason. The reason is, if something were by chance to go badly wrong, there is nothing to stop it going bang. Use 1 cell only, or do a proper machine shop job on it.