ahhhh they make 3 mk1 caps... a screw style... a german one, caddy/jetta and a westy one...
so will mk1 jetta fit a caddy... id say no and you probally wanna seek a westy one... just cause caddy was westy desgn...
why german and westy differ.. the teeth are for different diameter holes... the flange are different shape/inner id.. till you hae 2 side y side ou do not see this.. but caps either do no tfit or fall off if you get it wrong...
back in 94 no intewebz.. im sure between then and now some mising crate has been found.. and thats how some made it to market.. trust me it was a still existant number then.. but submitting a order monthly for almost 2 years with no fufilled.. i quit.. a truck of 100 would fill supply/demand for locking gas cap for caddy in usa for years... so yes.. you may find a few dusty ones... you kno was well as i do.. crap lik ethat went missing in those times...