They will take the risk because they cannot see it. If you manage to get it and it doesn't the evidence is there and they will walk away. It's a bit similar to RoS. If it's in the contract they will pass it on the assumption the client will honour it and fight it later. If you find out your client won't honour it they won't insure you regardless of what's in the contract.
I'd be surprised if any of the insurers are any different TBH.