Yes, they are parts of the hatch locking system. The interesting part is they are located differently to the kit but overall this pic has a lot of differences to the kit, but also many differences to actual period vehicle pics.
Compare the aspects of the cut out/raised area on the side of the bolted plate and the notch at the rear of the plate in the video capture to this pic.
Note also a prominent bolt on the gun mantlet not visible as a bump under the canvas cover in the video still. Then compare that pic to the kit:
Looking at the open hatch pic, it suggests the Amusing hobby hatch is too wide, and a commonly cited kit issue. However, look at the periscope cover on the left of the hatch-less pic, and its relation to the bolt (green circle) in front of it, plus the apparent width of the triangular segment to the scope cover’s left. Then look at how the section of turret on the right of the hatch tapers slightly at the front. Compare to the pic of the kit turret. Then compare the centreline on the raised section on the right close to the back end of the turret to the area in the kit (Yellow arrow) I think it is because the sections on the kit turret beside the hatch are too narrow, not that the kit hatch is too wide at all. Also the mantlet in the kit seems narrower than the one in the pic, which means if it was widened to fit a widened area on the hull beside the hatch, the rest would be in proportion!
Yes this is all based on one pic and perspective might play its part, but to my eye, I believe I’m on the right path (as opposed to confusing muddy water for bushes ( 
)