His spokesperson at State denied it on his behalf. Tillerson simply said he refused to even deal with petty stuff like that. And tensions or not, the media was putting out a lot of speculation I would label fake news during that time. I hope you are right that Tillerson was informed of the decision last week, but it still would have been better form if there had been a formal announcement with a congenial sendoff for Tillerson. But oh well. The President is himself and he does things his way and we elected him for the results he promised and is doing his damndest to deliver and, if he can do more of that, we really don't care what protocol he uses to do it.
Trump himself pointed to Iran deal as the major point of disagreement with Tillerson.
Trump wanted to do something about it (Obama was for it after all

) and Tillerson thought the deal was fine. Pompeo is supposedly more on the same page with Trump.
Trump is the boss, he calls the shots. Tillerson was not used to being subordinate to anyone, he was the CEO of Exxon Mobil, a huge job. It was a clash of egos, nothing more and Trump did the right thing.
We can argue the point that he did the right thing another day,,,,,It was how he did it Comey Tillerson who else did the yellow coward fire with not looking them in the eye?
Both Tillerson and Trump have been discussing this, eye to eye, for months according to them. Tillerson was advised by General Kelly last Friday--a couple of days before the Pompeo announcement--and he is still on the job during the transition period. The President has had nothing but good to say about Tillerson, but that they could not agree on a number of key issues, and the parting was mutual.
So I don't think Tillerson was disrespected in any way. I wish President Trump had handled the announcement differently, but in the grand scheme of things, that he didn't does not detract from the fact he is keeping his campaign promises to the best of his ability. He has accomplished much more in a short period of time than any President in my memory, and that is what we elected him for and not for his sense or execution of protocol.