Damn, you're right - the last craft has no gunner.
The RE-8 directly above your post shows only a pilot. But the last one in the second batch appears to have a gunner in the front seat. Are these the same plane? I can't tell.
These are all great pics. It's a good feeling to see so many WWI replicas flying these days. Now, if a decent percentage of them could gravitate to working in film, we could break the stranglehold of the much-modified Tiger Moth!