I know we've probably all tested in toilets/bathrooms etc but for them to suggest that should be where you do it is ridiculous, obviously I expect it's clean in there but the most unhygienic room in the building is where they are suggesting you go!? Madness!
Have you been in the job long? I'd be questioning why it's suddenly just become a problem when you've done it for X amount of months/years!
I understand some people don't like needles/blood etc but they would know what you're doing when you get your bits n bob's out and could simply look away!
What if your bg was so low you needed to test ASAP but instead you had to go and collect your bg monitor, go to the office/corridor/toilet, you're losing valuable time!?
I second Andrew's advice on suggesting they supply you with a libre if it's that much of an issue for them