Robertson didn’t assume responsibility for his actions, and nor did he care much when it was revealed the mother spider was scared and dying.
Noth’s character gunned the beast down and felt justified in his decision, despite the Doctor chastising him afterward.
That wasn’t the only thing that the Doctor didn’t like about Jack Robertson.
The brusque character had been using an abandoned coal mine beneath the hotel as a landfill dump for another his businesses, which is how the mutant spiders came into existence.