I agree w/some of this. Stephen Neal obviously screwed up the execution on that goal line play in Indy allowing the free hit on Maroney (he should have blocked Wheeler and left Brackett for Taylor). Baker was pretty pitiful vs Jax as well.
Beyond that however, I see some problems in Maroney's ball security here in both the Colt's and Jax clips. Ball security is a function of technique and some of those technique's are universal fundamentals and others come down to coaching preference.
One of Maroney's techniques here which may come down to coaching preference is his carrying the ball in his inside arm on both plays. Most coaches would prefer that their RBs carry the ball in their outside arm on a play like this to prevent inside out hits on the ball like what we saw in Indy.
Some coaches want their guys to always carry the ball in their outside arm and will require that the RB switch hands based on defensive leverage. Some do not allow their backs to ever switch hands and will start with the ball in the outside arm and will keep it there regardless of leverage. Others will mix and match a bit (only allowing switching in the open field w/no immediate defensive pressure for instance). Some will allow a RB to simply carry the ball in the arm they are most comfortable with, such as their dominant arm. Maybe Maroney is a lefty? I don't know why Ivan Fears has him carrying the ball in his inside arm in these clips (maybe he doesn't and Maroney violated his rule) but if Maroney is going to do that he has to be iron clad in his universal fundamentals and he isn't.
Beyond the grip of the ball with the fingers in which there are several different ways, the RB should have some space in his palm area and he must, must, must keep his wrist above his elbow at all time. Maroney is not doing this in either of these clips. He holding the ball down around his mid-section which eliminates several points of contact making it far easier to lose the ball on contact.
The universal points of contact are fingers, forearm, bicep, rib cage, and when in traffic, the breast plate. Holding the wrist above the elbow maintains contact with the first four. Not doing so means that the contact is only maintained with the fingers and forearms. Even a two handed carry there exposes the ball because the mid-section is soft and no real point of contact exists there.
When in heavy traffic and taking contact, the RB needs to shift the ball to the breast plate and bring his off hand over the ball to squeeze it tight to the breast plate, either horizontally or vertically.
Maroney does none of this on these goal line plays. He should add an addition layer of security by rolling his shoulder as he shifts the ball to his breast plate which we don't see here either. I'd also like to see him running lower in these situations for better ball security and more power.
Maroney has been a very good ball security guy over the full length of his career but he showed very poor technique on these plays IMO. Once the hand-off is made, it's the RBs responsibility to hang onto the ball no matter what. The hand-offs were made here so, at least in my philosophy, the fault lies with him.