Assume all facts in question are due to the ignorance of the reporter.
If someone goes through the trouble to make pipes and endcaps (they look a bit like Maglite bodies, where a lot of pre-made wink-and-nod "NOT A SILENCER!"-parts are sold online.) that are all properly threaded for a suppressor, that's generally the hard part. Drilling holes and denting out a stack of freeze plugs to make rudimentary cone-baffles is the easy part. And you can skip the coning process, trading some dB's for ease of manufacture. So I'll assume they were filled with either baffles, or perhaps at least Brillo pad.
Hollowpoints? As noted, illegal to sell in some CA cities, not state-wide that I'm aware of.
As to the LEO/Military Restricted marking, that's almost always on the magazines. And even if they're really "old" magazines, that makes them '94 ban era over 10 round mags, and over 10 rounds is illegal in CA in all circumstances, even "CA Pre-Ban" as of last year (NRA fighting in court...)
California laws not withstanding, what an idiot. Even if he was up to something purposely evil, doing
anything that's arrestable or cause for police contact when you're carrying a bunch of illegal hardware...
Oh... BTW.
https://www.walmart.com/ip/NTC-NTC0010-0-62-x-24-MagLite-D-Cell-Super-Combo-Solvent-Trap-Adapter-44-Light-Bulb-End-Cap-8-Storage-Cups-2D-Cell/581545626