The Yalkut Shimoni is an ancient piece of rabbinical literature dating from the 1st century AD that touches on a number of scenarios for the end times and the coming of the Messiah.  It covers the rise of wars, the coming of the Messiah (what we Christians refer to as the "Second Coming", and Jews see as the first, as they don't believe Jesus is the Messiah), and other related and similar things.  The problem is, the prophecy as a whole is wrong.  While there are a few parts that are correct, likely because some of the commentary is taken from the book of Isaiah, the prophecy in general is invalid as key parts of it go against established prophecies in Revelation and other books of the bible.  So since the prophecy must be taken as a whole and not in parts, it therefore by necessity must be considered debunked.