Can the case of the town police station be handled by the Municipal Public Security Bureau?

First of all, according to the normal filing procedure, you should report the case to the local public security department, but just suspecting that it can't be handled fairly is not enough to be a reason to go beyond the level.

When you think the result is unfair, you can apply for reconsideration to the public security department at the next higher level or to the local procuratorate.

Regarding whether or not to file a criminal case, we should not only rely on the equipment used to file a case, but also look at the harm caused to our loved ones. I suggest that your uncle do an injury appraisal. If it constitutes a minor injury, then the public security department should file a criminal case, otherwise you can appeal to the public security department at a higher level or the procuratorate.