And, sadly, once he saw it, and reasonably knew what the second one was likely to be used for
A couple of months ago, Bruce Shneier linked to an interview with a professional safe cracker. Relevant piece:
Q: Do you ever look inside?
A: I NEVER look. It’s none of my business. Involving yourself in people’s private affairs can lead to being subpoenaed in a lawsuit or criminal trial. Besides, I’d prefer not knowing about a client’s drug stash, personal porn, or belly button lint collection.
When I’m done I gather my tools and walk to the truck to write my invoice. Sometimes I’m out of the room before they open it. I don’t want to be nearby if there is a booby trap.
I think if Anaya was following the same rule, he'd be a free man today. Once the mechanisms failed to trip, he should have handed the gentlemen tools (drill, saws, etc..) told them where to drill and walked away.