holy sh!t was it making any weird noises before it went bang??? anymore damage???
Same happened to one of mine, your upper spring plate has rusted away, gsf do them, you can replace both rear shocks, bump stops, top spring plates and top bushes for under a ton
never had this on a vw....this did happen on a cavalier sri I had about 10years ago (and it was only 6 years old).. i have never bought vauxhall again and on that the whole top mount area had rusted away