With the injury situation at that position, is it becoming thin?

Prayers to Zac Clark, Derek Roback, and the other TEs who are hurt. 

what kind of injurys do they have?

Troy Hill had knee surgery before the season and won't play this year.

Derek Roback hurt is back in the summer and is expected to return probably next week for Kent State.

Zac Clark hurt his knee against Marshall. No official diagnosis yet, but didn't look good.

That leaves starter Jordan Thompson and JC transfer Tyler Knight as the only scholarship players. There's also senior walkon Joey Inks, who converted to a tight end this summer (but mostly plays special teams), and freshman walkon Andrew Pepin on the roster.

I would think it would be more likely we'd see one of the running backs there, like Inks, or Favors or Dallas Brown.

Nieco Teipel was listed as a TE on the spring roster.

Colleges and even the pros have used offensive lineman as blocking tight ends. Most have concrete hands but a 6'6"-300 pound Ryan McGrath would be a sweet TE blocker....or 6'7"-290 pound Mike McQueen who may be able to catch since he's a former basketball player....true freshman however probably out of the picture since they want them to keep their redshirt eligibility........even though 6'6"-250 Andrew Bennett was rated by places like scout and rivals as a TE.