WAG here, but is it possible that an EM VW bus "church key" used to open the fuel fill and rear engine hatch might work? I know they're often used to replace the missing ones on Crown skoolies. Two styles, a "T" and a "P", cost is around $15 or so. Below are a couple photos of them.
Just thinking outside the box a little. . .
FWIW & HTH. . .
