Hello I have reviewed your query and I am afraid it is not great news. The property is the responsibility of the landlord and not the agent so the landlord does have a duty to ensure that things within the property are liveable and maintained whilst the agent just has to manage the property. This means as the landlord , unfortunately, you would have to bear the cost of the damage.
However; the contract you have provided does state under clause 3.5 that the agent must return the property in a liveable condition. It does not sound like he would be doing that if the damage remains, therefore you may have a breach of contract claim against him if it can be shown that the property is not in a liveable condition.
What I would suggest you say to the agent is to point out clause 3.5 to advise that although the property is your responsibility that if it is returned to you as it is, it is in breach of the contract therefore he has to rectify it. It will then be up to you on how you wish to proceed, whether to take him to court for the damage or not. I must point out though that this may be a risk.
Another option you have is to use your insurance if you have one to help pay for the damage.
Another option going forward is to rewrite the contract for future , so it is more favourable for you so you can avoid this situation in future and include a clause that if the agent chooses tenants which destroy the property then he will be liable for the damage.
Lastly, the tenant that caused the damage, I presume they paid a deposit so the cost of the damage should have come out of their deposit. The agent should have ensured this happened. If he did not, then you can also have an argument that the agent has not acted in line with his duties and make a complaint about him to the property ombudsman or the trade body he is a member of. You can also request details of the tenant who destroyed the property and sue them for the damage, as this is what a deposit is for and if they haven’t paid for the damage then they would be liable , this should also be in their contract when they started the tenancy.
I am sorry I could not provide more positive advice but I have a duty to be honest with you and these are your options. I do hope you find them useful.
Please kindly provide a rating for my answer by clicking the stars at the top of the page. Thank you. John.