I had it too ! At the moment I went there to ride it, I didn't know that there was this kind of restriction, and the operator said nothing to me ! Few years later, I read on french boards that this coaster is a children-only ride !
But this restriction is rare in Europe ! I miss a credit at PKI too ! And that's sure I'll miss 1 at Knott's, and 1 at SFMM ! Hum, and few more at SFMM, actually !!!
At Cedar Point, nothing is forbidden to adults ! When I went there, the operators were so kind to help a so big man like me entering in the so little car of their kiddies ! Then, I have had the full credit !