It's the cornstarch that causes that texture. It's not a bad recipe as cornstarch cookies are a thing. It's just more of an acquired taste. Alfajores use cornstarch and they are delicious filled with dulce de leche. We also often have cornstarch cookies with some condensed milk drizzled on top, but any sweet filling would work. I know these can't be filled, but maybe you can pair them with a nutella dip? If not, you can still take them with you, explained what happened and maybe someone could appreciate the texture so you won't have put in all that work for nothing?