Why would someone use a face and hand cream, which is intended for external use, to do a pelvic examination? It might not hurt her, but it is definitely not a product designed for that use. There are purpose-designed products, like KY Jelly, that are intended to be used as lubrication when inserting anything into a woman's vagina.
Nivea is not dangerous or anything, especially if it is clean (squirted out of a bottle versus dipped out of a tub). But it does not seem very clinical. Why does the osteopath put his fingers in her vagina, is it a once-a-year or once every three years thing like a pelvic exam? I have only once or twice had a doctor put actual fingers in my vagina, the older-fashioned kind of pelvic exams used to involve a little of that for the reason of feeling the ovaries by pushing on the same time at the outside of the abdomen. Is that what the doctor is doing?