OP.
You are required by the Occupiers’ Liability act to take reasonable care to make sure that visitors are safe in the premises that you occupy. This is your responsibility, not that of your landlord, but let’s say that the bannister was defective or a ceiling tile fell in her head- you could say that it was reasonable of you to have expected the landlord to maintain that.
On the other hand, let’s say you had left spilled oil on the painted wooden stairs and the cleaner slipped- that would be on you.
However the cleaner also has to take reasonable care eg not wandering about with headphones on or looking at her phone. If she was not taking care then any award could be reduced/extinguished to reflect contributory negligence.
The insurance your cleaner said she had will be mainly to cover her liability to you eg if she damaged your clothes or furniture, or to your landlord if she damaged a wall or window.
she’s unlikely to have insurance for loss of earnings. But if she does, those insurers could in theory pay out and look to recover from you.
If she has injured herself in a way which means she is permanently disabled or takes such a long time to recover that she can’t work for an extended period she may well look to make a claim. That claim will only succeed against you if you did not take reasonable care. She also has a duty to mitigate her losses eg by taking on a desk job.
People who go to no win no fee lawyers tend not to be advised to proceed unless the defendant (ie you) is insured because the no win no fee people can’t be sure you’ll ever have the money to pay the claim, which is what pays their fees when they take a percentage.
In summary:
- any visitor to the premises you occupy can claim against you regardless of the fact that you are not the landlord and regardless of why they were there
- she has to suffer actual losses in order to claim.
- her own insurance is unlikely to be relevant
- she probably won’t sue you unless you are insured.
- if you took reasonable care you can defend on that basis so start making notes now, take photos of the scene etc
- She also had a duty to take care.