Just a supposition, wouldn't it be enough using just udev?

I mean if you add a row in fstab

### /etc/fstab
....
/dev/sda /mnt/usbdisk auto noauto,user,sync 0 0
....
### EOF

then probably it would be enough to add a line for running a program
when the stick was plugged in

### /etc/udev/rules.d/50-udev.rules
....
BUS="scsi", KERNEL="sda", ACTION="add", PROGRAM="/sbin/mount
/mnt/usbstick"
....
### EOF

is it possible? of course maybe it would be better to add a user rule
for the particular usbstick model...