Not sure why he would be forced into it? His credit card got refused earlier in the episode. Glenister was just a bit of a southern gob-shite pretending he was rich. He probably needed the cash the scam would generate.
Thought the ending was great personally and was light-hearted as we initially thought the other 3 were going to kill him to keep him quiet.
Alot of the inside number 9 episode have sinister endings. This one was a happy ending for all involved (except the guy at the end getting scammed
)