That bugged me a bit, but given the nature of the boat they maybe had limited options for alternate paths and perhaps figured they could get past it? Presumably not the first time it's happened if they've been there for while.
To be honest, I thought the 'Kane turning up the mindflayer on Dr Pershing' thing a few episodes back was more daft. Not sure if I missed something, but surely it would have been glaringly obvious that the reason Pershing had somehow been properly mindflayed instead of just 'refreshed' was that it got turned up to 11 and the obvious suspect would be the other ex-Imperial person left in the control room by herself?
On a different subject, I've been meaning to ask, I haven't watched any of the animated stuff, and I'm gathering I'm missing a fair bit of back story and references to it in this and the other live action shows. Not sure where to start with it though. I had a quick google and there seem to be a bunch of different answers. Any recommendations?