That does look ok for a Thomas' rather than Red but the tip of tail and feet are obscured in this picture and it's difficult to tell if that's just shadow on the nose or dark pigmentation. Those are they key ID features to look for. The size difference is obvious in the field too especially as there are Reds around commonly and Thomas does appear smaller.
This one I'm sure is a Thomas' Flying Squirrel - if you enlarge the picture you can actually see the two (hind?) feet.