Wow! I just have such a different take on this thing. My interpretation is that he loves you. He is busy. The vacation confirmed in his mind that you love him too, so...whew! He doesn't have to worry about that anymore. He feels secure in your love and he hopes you feel secure in his too.
Daily contact? Meh, not necessary if you both understand. Like for instance, if he calls you on Monday and you have a nice conversation and he says, "I am super slammed tomorrow."...don't expect a call the next day. He told you he is really busy. Why do you need to have so much attention? You turn yourself into an obligation IMHO when you start demanding he talk to you every single day. And he already said he is Very Busy, so now is the time for you to show empathy and compassion that he is spread very thin. He will appreciate that and love you all the more for giving him space.

You aren't giving him a chance to miss you! Get busy and stop obsessing about what sounds like a good situation. He's had a lot of hurt in his life, so just knowing you are there has to be a comfort to him.

Let him sort out his time in these next two weeks and then wait....yes, I said wait, for him to call you. He will crave to talk to you if you are busy with your own life, and he will be wanting Your time for a change.

Again all this is IMHO Best to you