It seems to me with the full teaser trailer out that the guy is not going to be playing anyone from the original timeline, or well at least anyone we have heard of before. Which brings me to a total nerd thought:
So who was/is John Harrison in the Original timeline? Will be interesting discussion after we learn more about JJ's John Harrison.
Unless, yes, it is just all a jerk off and the guy is some fabled TOS character. (Ugh)
"I'll break out of this zoo somehow and get to you. Is your blood red like ours? I'm gonna find out. "-Captain Christopher Pike