Unfortunately it is just not practical to expect the nursery to wipe her. For several reasons: Firstly ratios do not allow there to be a member of staff constantly in or near the bathroom. With the new ratio law changes this will only get worse.
Secondly child protection. Unless the child actually asks for help- staff cannot go around asking & randomly checking toilet trained children. Obviously if they smell like there might be an issue they would take the child to get changed & supervise as they clean & change themselves. But taking a fully capable child for random pants checks would put staff in a very inappropriate situation.
They can help remind those who have the odd accident, remind them on what they need to do. Because the ideal scenario would be for them to become fully independent rather than getting them to constantly ask & need help. This is something you need to practise & perfect at home.
The best hope the nursery has is to regularly ask & monitor the best they can.
At our school we try our best to keep an eye on who is going in there, remind those that need it, help 'talk children through' the process of wiping themselves independently. Role play & practise good hand washing technique. Work with parents so that they support their child to practice these skills as home.
So - take your child to the GP & tell them about the constant worms, follow all the instructions to treat it (all the necessary laundry etc...)
Talk to your nursery about ideas for improving the handwashing- there should at least be a member of staff supervising them washing their hands at snack/lunch times. Make a suggestion that they could perhaps do some talk about this at carpet times.
OFSTED would be looking for how they promote healthy habits to the children, so that might encourage them to take it seriously. If they are one of these nurseries that opts to use that sanitising gel instead of handwashing- explain that they need to be teaching the children to wash their hands- it is in the EYFS & an OFSTED expectation that it is part of their provision.