Keep Mattison, cook is farrrrr from guaranteed to play the whole season. shit if cook does get hurt you have your rb1 for playoffs.
as for TE, I like in this order jonnu->goedart->hock. Remember last year hock had a great week one and then disappeared. and tbh there are way too many targets to get a workload per week (kerryon, swift, ap, jesse james, jones, dola, golladay all worth targets) Goedart will have his games but you def cant expect to outperform ertz or even keep up with ertz plus the entire offense was injured. Jonnu has aj brown as competition for targets, thats it. I think jonnu was a top 10 TE last year under tannehill as well.