The "distrust" you sense isn't really distrust, it's the understanding that all military intelligence is vetted before it reaches the public. In particular, they're extremely careful to disclose any information that would compromise operational security - especially as it relates to aerospace monitoring. The reason for this is that any observational capability of the US to detect objects at high altitudes/speeds influences the nuclear strategy of other nations (ie, if you plan for a first strike, you plan around the known capability of the US to detect it).
And that's where the skepticism comes from. Any disclosure about what was observed, how it behaved, and the conditions of the observation have real world impacts on US operational security, and any information regarding that should be taken with a massive grain of salt.
Basically, treat public intel from the military as a secondary source - not a primary one. That doesn't eradicate its value, but it puts more onus on you to be critical of it.