There's definitely a screw-head there. Apparently, the op-rod on this one is a two-piece unit. Also, the trigger-housing bottom appears to be 100% machined from billet (not forged & machined)
This was NOT a Denix "resin replica". I operated the op-rod, which retracted the bolt. It was 100% wood and steel, but I could tell it was an "aftermarket" copy of some sort, kind of like a late Universal M1-Carbine.