Anyway, I am not familiar with all the terms of those prior agreements you cite but I was not aware that they specify where foreign embassies are to be (do they?).
The agreements themselves may not specify where foreign embassies are to be located, but the language of those agreements effectively drives the legal and diplomatic decisions in many countries that have embassies in Israel (including the U.S.). The U.S. has a long-standing policy, for example, of refraining from placing an embassy in disputed and/or occupied land, and the language of those agreements I referenced leaves the status of Jerusalem in a state of uncertainty. I suspect most other countries have similar protocols, since no other country that recognizes Israel has an embassy there. Even some nations that previously DID have embassies in Jerusalem moved them to Tel Aviv for political/diplomatic reasons related to the uncertain legal status of the city.
Because of the uncertainty of the legal status of Jerusalem, putting an embassy there is like building a house without having a clear title to the property. Nobody in their right mind would do such a thing.
One was murdered in Israel less than a year ago: Taylor Force, US Army veteran, West Point '09 served in Iraq and Afghanistan. He was enrolled at Vanderbilt and doing graduate studies in Israel at the time. His murder was praised by Hamas. Force's wife was stabbed also but she lived, I believe. Let's all get on the same side and kick terrorist ass.