Although I'd be keen to help clean, I would remember A. that this could turn into a regular, and B. that you live so far away, help might be impractical.
I do think, though, that the child should be first priority. Whilst I think grubby playtime, mud pies, spilt food are all part of childhood, no child should smell bad. It isn't hard to keep a child relatively clean, simply by regular nappy or potty times, and doing sufficient laundry for a change of clothes.
I think my children would want me to take over at bathtime, and maybe nappy/loo times, or rather perhaps they would expect me to want to! (Do I??) However, I would find it hard to suggest a daughter deals with cleaning the house, but I definitely would if I thought food preparation and eating took place in dirty surroundings.
I think I have mixed opinions here but I would mainly be concerned about the child. Most important.
If someone chooses to have a child, the responsibility of care falls to them but, in your position, I would keep in mind that things could deteriorate further, and surely nobody would want that.