Unless you think he blindfolded them and forced them into his car, wouldn't it be safe to assume he did ask if they wanted to go? How else did they get there
Idk man my parents were always dragging me to shit I didn't want to go to when I was younger. Yeah I knew beforehand what it was but it's more of a "we're doing this" rather than a "do you want to do this?"
Everything is possible in Fantasyland that happens exclusively in your brain.
Why does it make more sense to assume his entire family for some reason drove out there without listening than that he never told them what it's about in the first place?