Other mistake: The guy who plays Clive in this episode has one of the most appalling accents I have heard. He's apparently from Manchester, but sounds like a sort of cockney South African. His accent slips around all the time; it's very poor. I wouldn't normally submit it, but his is so shockingly bad I doubt anyone would be fooled into thinking he was British.
Suggested correction: I think this may have been deliberate. The episode is almost meant to be ridiculous, with the characters quickly churning out lies on the spur of the moment, and everyone supporting the fake family story without objection.