What you should be able to do is to develop a small custom app that uses the print reader's SDK to read a fingerprint and convert that print to a unique identifier according to your project's need. The actual print reading should be guarded securely for the privacy of your users.
You can then call this custom app from Collect and return the unique identifier to Collect once the print has been identified. Documentation on using external apps can be found here and there's an example project here.