I don't think any one can answer that without seeing the state in which you left the house. Not saying you have not done a good job at cleaning but who knows. (in my opinion you should always use professional cleaners for vacate cleans to avoid situations like this one)
If the agent has taken photos and taking you to court it means there confident they are doing the right thing for there owner and will win Agents won't bother if they think they will lose as if there is any grey area the courts mainly side with the tenant
Sounds like you have aggravated the Landlord in some way? breaking a lease always frustrates an owner Were you a good tenant? as in easy to please and paid your rent on time? 5 years is a decent time as a tenant
From my experience if the tenant has not been good than they break the lease the landlord will go after them for everything they can not because they want to but because they have to as it disrupts there own loan repayments (these days no one can afford that)
its not personal everyone is just trying to protect themselves as being a landlord in this day is getting more and more expensive
