Pretending to be an unknown and never-before-mentioned team of dentists arriving (at night) to handle the most important animal in the zoo, without it being scheduled because of an emergency procedure no one knows about that's being done without its normal caretakers present seems
easier to bluff than some electricians in a van full of electrical gear arriving after a reported malfunction of electrical equipment? (Please do make place to fit in a tiger; but cats are pretty flexible, no?

)
The construction crew's placing magical walls, not electric security cameras. Would surprise me if it's the same company, but it's a possibility I guess. Although even then I hardly think the guys who treat -quote from SR4A- "notoriously sensitive and difficult to maintain" magical plants are the same guys who also deal with the security sensors and electrical equipment... (That might explain why the security seems so easy to circumvent.) So they'd still need to make a call.
As for the van, pig's got a maintenance van. Sounds like what we need. Not the right colors, true. But they're there when expected to be there; they're a team sent there to deal with an emergency repair, wouldn't surprise me if that's not the same guys that do the electricity during the day shift. They could be working for the company with subcontracts -any company would rather have some people there instantly and pay a little extra than risk a breach of contract for a security-system that breaks down before it's actually in use.
Agreed, if no call is made or we can't intercept the call and say something like "Hey, you're in luck, we've got some of our guys nearby who just finished a job in the neighborhood, we'll send 'em over right away." , the plan's a bust.
So yeah, worst case: the two stealth guys get out, no alarm or suspicion was raised, all other options are still open. Doesn't really seem that bad.
Problem with knocking out or jamming guards: spider or guards might notice.
Problem with knocking out spider: guards might notice.
For all we know the 4 of them are chatting over their comms the whole time.
Once we do either of those, we need to either take 'em all out quick and clean or we need to get out before help arrives.
And just one small remark: what if the spider repairs the stuff himself instead of calling a tech crew?
Doesn't sound like a spider's job to me, but if he did, wouldn't that be awesome? That spider's the trickiest part of security afaik. If he logs himself out, the whole security system's even weaker than it was before, no?
"look like a malfunction": find electrical wire, melt with miniwelder, must've short circuited. Sure, CSI would find that the temperatures aren't really right and the flame seems to have come from the outside; but if a electrical wire in a brand new system melts and there's nothing else missing or damaged in the building, who's going to be very suspicious?
So uhm, does the rigger semi-hacker think he can pull it off? If no, this whole issue isn't important anyway
