Ennis is in fact looking down to avoid Jack's mouth, and Jack is looking at his mouth, whiCh he'd like to kiss, but isn't gping to msakeTOO a big deal out of just now. It is Jack who grabs Ennis's hand, twiCe. FiRst. his wrist (you can clearly see the bluie cuff on the grabbing hand), and then, right before his head collapses on the tent foor, he brings his other hand across his body, and grabs the back of Ennis's hand with that hand as well. Ennis never grabs a hand. You might make out a case for the first grab being for balance, but--the second one?
I have spoken!