"I wonder what the message was that got the other MPs to decide to respond to a stranger?"
It doesn't seem as if they needed much by way of prompting -
"Wragg said he handed over personal phone numbers to a person he met on Grindr. Those colleagues were sent unsolicitous flirtatious messages from senders identifying themselves as 'Charlie' or 'Abi'
Two MPs responded by sending an explicit picture of themselves"