Difficult question. I think Marinelli has done more than Linehan, but I can envision more replacements for Marinelli than for Linehan.
I think they both stay. Leslie Frazier was NOT fired in Tampa. Jerry will likely keep Kiffin around if Marinelli stays, but it's doubtful that Tampa would pay to bring Kiffin on as a consultant. Marinelli's "loyalty" could play into this in the opposite direction that the media portrays. He is probably as loyal to Kiffin as he is to Lovie.
The longer the Cowboys stay in the playoff, the lower the chances of Linehan being a Head Coaching option. Most teams want to get that resolved before the Super Bowl. Linehan had an 11-=25 record as a Head Coach.