1. PrezZelenskyy needs not apologize to PrezTrump for what had been a forthright straight-talking discussion. However he needs to apologize to PrezTrump for wasting his time on a meeting for speaking about matters other than what was the agenda intended, as PrezTrump' time is limited. He does not run UKR, but USA as well as being a Free World Leader, with very much concerns daily to attend to.
At the least, PrezTrump did the right thing to end the meeting within 10mins after wasting such precious time to explain, & he did diplomatically still invited PrezZelenskyy back when he is ready for the agenda, as well as PEACE in UKR that is at the top of his mind.
2. The only one that PrezZelenskyy SHOULD APOLOGIZE to is SecState Rubio. As the US SecState - the direct representative to foreign nations leaders, it is his job & responsibility to ensure the President's time is not wasted, & any issue that is NOT on the agenda & purpose of meeting, be left out.
Unfortunately, PrezZelenskyy DUPED the US SecState that he would sign the mineral deal with no other conditions. What eventually transpired was not what was spoken taken at face value, & thus chaos descended....with US SecState now in deep trouble with PrezTrump......
It is NOW no wonder that some members of US Congress had publicly spoken that UKR is not a country that USA would want to do biz with anymore......