Hey, Bill,
I would imagine those are the ones. In all my years of research, I've never come across more than 3 pictures of Titanic at Cherbourg (the 2 above-mentioned ones and that evening-time one that is so heavily retouched it looks like a drawing).
I do believe that the night picture of Titanic really is a photo - the errors that Dave Gittins suggest are liely from the hack-job retouching that the person did. Yes, the window configuration is wrong, way wrong, but I firmly believe it's the bunged-up paint job.
As Daniel K. says: As is with (amateur) night photos today and even more so in 1912 they didn't turn out too well, so they were given some work, and now they're unrecognisable and only look like drawings.
If you look at the stern end of the ship, the smokestacks and the land in the background, this, to me, does look more like a photo. A lot of the retouching work appears to have been done to the portholes, windows, open prom deck and especially the water, and the light configuration is not consistent with the actual Titanic.
Just my .02
Dan