Was the deposit protected?? Have you advised the scheme of your intentions??
Was there an agreed (eg signed, dated by tenant) moving in inventory with full, detailed, descriptions and photos?? Ditto move-out?? If so you've a chance: If not forget it, you'll likely lose any adjudication.
20 year life for carpets, wooden floors, anything else damaged?? Some might say that that view of 20 years is very over-optimistic & would be "betterment" & unlawful.
Did you get estimates from cleaning companies for removing mould??
Were there any inspection reports during the tenancy?? What did they say about cleaning & conditions??
I am legally unqualified: If you need to rely on advice check it with a suitable authority - eg a solicitor specialising in landlord/tenant law...