Adhesive for glass mosaic tile

Hi. I just came across this forum and could really use some help from someone who knows how to install mosaic glass tile. We just installed some glass mosaic tile as a backsplash in our kitchen ourselves. The instructions said to use latex modified thinset, but my husband, on his own, decided to use TEC double duty ceramic tile adhesive instead--I think a salesperson at Home Depot talked him into it. Has anyone ever used the TEC product instead of latex modified thinset to install mosaic glass tile? If you have, did it hold up? If you haven't, do you have an opinion on whether our backsplash is going to fall down? Thanks.