There was considerable damage to yours, and your acquaintance's, gear. Do as has been suggested. First, find the culprits and offer them a chance to make things right. Second, keep the pub owner (or whoever) in the loop, but offer him a chance to make things right. Failing either or both actions, get a sympthetic lawyer to rattle their cages. Your own insurance (I trust, since you didn't mention it) is non-existent, so get some now.
It strikes me that where I live this would have been a criminal act and the police would have been involved. I'd say get them involved.
Last and worst case is for you to pay for damages, but you will need to pay your acquaintance asap and look for compensation from the guilty parties later. Whatever happens, be entirely up front and honest and do everything you can to make things right.