Discolored And Thick Toe Nails. Suffering With Alzheimer's. Does Polishing Nails Harm Her?

I am the daytime care giver of an 85 year old woman who has Alzheimer's. Her toes are gnarled and some cross over the others. The big toe nails are very thick and discolored. A podiatrist comes to the house every three to four weeks to trim the nails and work on the bunions. The young lady that stays nights has polished this woman's toe nails. I don't think it was a good idea but wanted to ask first if this could harm the nails. The podiatrist won't come for another week.