Here is the situation:
The ramp was damaged and partially collapsed in 2004 from snow and rain damage. Israel is going to repair the ramp. Israeli law requires that before any construction can take place, an acheological recovery must be made. This is done to ensure that nothing is lost or damaged during any construction.
UNESCO inspected the excavations and said everything is being done professionally and there is no danger to any of the Muslim structures. The reason why UNESCO is asking that the work be stopped is because their standard for the construction is lower than Israels. They say that "the excavations should be limited to the stability of the structure needed for the consolidation work. "
Israel is trying to protect any artifacts that are there as required by Israeli law. So since Israel is doing a more complete job than UNESCO thinks is necessary, they ask for the digging to halt. That makes sense...
The bottom line:
The UNESCO report says all of the work is being done safely and professionally and it poses no danger to any Muslim structure.