The history of this conflict is pretty messy when you dig down into it, isn't it? It's long and complicated enough that either side can create a compelling narrative to justify their national interests. I appreciate that you delved into it. You might also be interested in the greater Cold war context of this conflict.
Nasser was keenly aware that his actions would trigger a confrontation and war with Israel:
At the end of May 1967, Nasser claimed in a public speech to have been aware of the Straits of Tiran closure implications: "Taking over Sharm El Sheikh meant confrontation with Israel. It also means that we are ready to enter a general war with Israel. It was not a separate operation."
He did it anyway. Claims that he didn't want war seem odd to me considering all of his public statements at the time. Perhaps he wasn't ready for war just yet, but his intentions seem clear.
annexation of land is a violation of international law, either in an offensive or defensive war. It is not a “grant”, it’s that state’s land to begin with.
Access to annexed lands would have to be granted by Israel because Israel controls and de facto owns them. International law is relatively meaningless if one cannot enforce it. Egypt got Sinai back via treaty and Palestine would likely have to do the same.