I already did in my post. Personally, I'd prefer to roll myself or see the roll so I can make sure that I am able to take full advantage of the halfling's Lucky racial trait.
Actually looking at it I guess the escape DC is static and there's no save or anything. If it bites it grapples. Sort of sucks if you feel obligated to escape, as it bites, grapples, then you have to spend your action getting out, then it bites, grapples, repeat.