Sorry I missed your post, You've probably moved on by now but I still have a set of those Caribou's if you are interested.
https://www.yamahasupertenere.com/index.php?threads/caribou-35l-side-cases-hepco-becker-racks-price-drop.22222/
The mechanic is probably describing the immobilizer which is the key switch & ECU being "linked" electronically for security reasons.
You would also need to be able to remove the two bolts holding the switch in place. These are tamper-proof where the head of the bolt snaps off after being...
Not trying to start a debate or criticize your choices but, just out of curiosity, what brand, weight, and frequency do you change your engine oil? ::)