Why don’t you escalate through your My Tesla account? That’s why that feature is there, as far as I’m concerned. I’ve had my issues with the Vancouver service centre in the past, took nearly 9 months to get a new windshield, but my issue was ultimately resolved and I’m sure yours will be as well.
They certainly seem disorganized and lacking in communication sometimes, but you never know what’s going on internally when you’re on the outside. I’ve worked for a company where despite my best efforts things would go wrong and parts wouldn’t show up or paperwork would get lost and commitments I had made to customers would go unfulfilled. I prefer to give people the benefit of the doubt and unless it is safety-related or has a negative financial impact on me, patient and courteous follow-up is usually more effective than ranting.
I’m sorry for your frustration and I hope your issues get resolved soon.