Trying to predict anything in either the show or the comic is a mug's game--I don't think anyone's EVER been correct. Kirkman's just that slippery.
That said, though....
I think they're going to need to pick up a few more warrior-caste level characters before getting to the prison if they want to have the manpower to clear the place out. As it is, Rick, Michonne--assuming that she meets them before they hit the prison--maybe Glenn, Daryl, and maybe Theodore Duggs are about the only hand-to-hand fighters they've got. Tough to imagine just the four of them being able to clear out the prison if it's anywhere near as infested as it was in the book.
good point, but i think its entirely possible that the prison will have more than just 4 people still alive inside. it gives them the man power to clear it out and also gives them some redshirts to kill along the way.
i just really hope axle makes it into the show.