Is there an OPSEC violation reporting POC to whom someone could direct me?

You can reach out to the COR for that Contractor. You can also reach out to the base security manager.

I would provide the info to the IG. If you know who the COTR or KO are, write them an MFR with screenshots

Start with your unit security NOC/Officer. They should know whom to contact in the contracting system. Each government contractor with employees holding clearances must have a corporate security office and officer. They will eventually end up handling the situation.