I had a similar issue with my set...the glass completely came off and fell on the freeway, I ended up buying the reps on Ebay after realizng how much money I had wasted for what I thought was superior quality, I would suggest using this double sided tape since its super durable and meant to deal with extreme weather and is rated for outdoor use, it may only be a temporary fix but I would suggest a liquid type glue meant for glass as a permanent solution. I use this tape for my spoilers and wings and it has always held up for years in the rain and it held my CF window spoiler to the glass for a long time now:
