The Golan Heights for decades belong to Israel, and will belong to Israel for ever.
Israel is too small to cut it for all the people that desire to make peace, and most likely broke it, non of these proposals ever gave something but peace to Israel, which is undoubtedly a good benefit, but nothing beyond that, and usually broken, Jordan however gave up on the WB and benefit from Israel the same goes for Egypt.
The Syrian are in same position as Gaza, to make demands with Israel, and can give nothing to Israel, despite the fact Syria is bigger than Israel at least 8 times, a small district such as the Golan Heights will only reduce Israel's military abilities with Lebanon.
It is a fact that Israel is the strongest country in military capabilities compared to Syria, in the past, and so in the present, and risking IDF to support Assad which is something some people already rushed to blame Israel in the beginning of the civil war, does not serve any Israeli interest at all, neither supporting the rebels by the way.
With all the respect to the Russians, Israel posses not only a powerful technological advantage, but also nuclear firepower, and probably one of the best intelligence capabilities if not the best in the M.E., I see no reason for Israel to be the compromising one in this case, specially since Syria have shown zero interest for peace in the past.
Looking at the current situation I can see a way where IDF intervene for Assad, and provide medical aid to the Syrians, with a peace treaty, handing the Golan Heights permanently to Israel, normalizing the relationship and establishing a good economic relationship, Israel would enjoy oil and perhaps some industrial manufactures will invest in Syria providing more work space and tax for the Syrians and establishing export-import, and in the future some Israel high-tech and even cooperated developments can be easily made to also cure the Syrian economy, in addition to form a future alliance such as Israel-Jordan.
One enjoy and the other does not miss a thing.