OP here...back for more advice. This creak is certainly the chainring bolts. The problem is that they do not tighten completely. The outer bolt head has a 5mm hex but the inner part is completely circular so there seems to be no way of getting a tool on both ends to tighten (no hex, no slots). I can't remove the bolts as the entire bolt/nut assembly just spins. Any ideas? Drill it out and replace or is there a way to tighten these?

This is a cheap truvativ crank from 2006