I was wondering if this plant needs to be in the Hylotelephium rather than sedum?

Sure looks like it. When I was changing all of those names, I could only change cultivars with species names attached, and I couldn't find any references to the species of Thunderhead. Now I found a source that calls it Sedum telephium, so I'll make the change to Hylotelephium telephium subsp. telephium.

Thanks for finding this.

Just saw this when I was loading photos.