Ask the agent for a copy of what you signed. The contract should AND TR1 should have been witnessed.
It could cost you if you don't complete - if that was the contract (and depending on its terms) you are technically in breach if you fail to complete. The purchasers can claim damages off you - for example, for hotel bills if they have to move to a hotel until you complete or wasted costs incurred.
Can you not get an emergency appointment sooner? The longer you have to wait, the more potential damages you will end up paying. Have you managed to organise getting your stuff out?