Platanthera shriveri (?) (Shriver's frilly orchid)

When Jim Petranka told me he had photographed Platanthera grandifolora last week up on the Blue Ridge Parkway, I said, "WHAT!?!". Platanthera grandiflora in that area of North Carolina was at peak bloom the second and third week of JUNE. I know that, because I photographed them the last week of June, myself. And he photographed these plants -- at peak bloom -- the last week of JULY.

He told me that he had some of the images on his laptop, and I asked him to show them to me. When I saw his images, I decided that what he had photographed was probably the most rare Platanthera orchid in North Carolina -- Platanthera shriveri. Of course, I had to see them myself, so I followed him to the location which was a couple of hours away. Most of the flowers were spent, but there were a few plants with presentable flowers toward the top of the bloom stalk. I'm fairly certain that these are Platanthera shriveri, but I'm open to any convincing that they are Platanthera grandiflora. Considering the bloom time, when P. grandiflora, P. psycodes, and P. lacera have been out of bloom for more than 4 weeks, what else could these be?