If this was true then the Israeli media would have been all over this, unlike the arab world the media in Israel is quite free all the major tv station (Channels 1, 2, and 10) and newspapers (Yediot,Maariv and Haaretz. exept Israel Hayom) are anti government and lean to the left-extreme left in the political spectrom. so my guess is if that sort of thing would actually happened then it would have been all over the news.
I am not saying that Israeli skies are impregnable, what I am saying is that anything that comes from a rv station that has Bashar Al Assad face as an icon on the right side of the screen souldnet be taken very seriously,my geuss is it was probably just propaganda to raise the Syrian people spirit.