Body oils are not in themselves fluorescing. No UV source will help you in this regard.

Notwithstanding the value of the film itself, you can use an indirect method of 'lifting' contaminants from the surface with a suitable adhesive material if done carefully. In fact, I have used 3M brand Magic Tape™ for this and similar things.

Here's the official Dick Tracey's Crime-Stoppers fingerprint lifting technique:

You will use a soft high-quality brush like ones used to apply facial make-up.
You will use super-fine powdered charcoal.

• Lightly "Dust" the surface of the negative with the powdered charcoal using the brush.
• Blow the powder from the surface. Some will adhere to the oily print on the surface of the film.
• Use a strip of the adhesive tape to cover the surface with the charcoal-coated print taking care to avoid folds, creases, and bubbles.
• Remove the tape from the film and the material will remain on the sticky tape surface.
• Put the tape on a clean filing card for examination and convenient storage of the evidence.
• Repeat for the more sensitive emulsion side of the negative.

The recommended tape will not leave residue. In fact, I have used the technique to remove problems rather than rewash and dry the negatives. I have worked with 35mm transparencies and saw no ill effects from this at high magnifications.

Good luck.