Does airport fingerprinting compromise my biometric security?

Access by a criminal? probably not much - if they can get physical access to your phone, access to your fingerprint by social manipulation or threat isn't that hard.

Access by government agency that confiscates your phone? theoretically yes, but no more than using printed fingerprints on an arrest record or lifted from your home and printed so they can be used on your phone.

Access by a local sheriff/corrupt cop? a lot of hassle compared with getting access to your finger