I will add a different perspective. We were trying to keep our old S70670 going but one day it just up and died. So I called Grimco (this was late October 2023) to see about getting an S80600. There was a promo going on with very favorable pricing, and so I said let's go ahead. Then they checked availability and it was zero. But they had a number of units on the way that were in transit across the Pacific, and three of them were headed to a nearby PSP who was just replacing 2 year old S80600s. So they called that company to ask if they could divert one of them to us, which they agreed to. Less than a week later it arrived. I unpacked and installed it myself (it's not rocket surgery, and I had done the same with the S70670 over ten years ago) and Grimco sent someone to go over the machine with me a couple of weeks later, which was the next available appointment. I was very grateful to Grimco that they went out of their way to get a machine to me, and thankful to the PSP (of which I am a customer for grand format prints) for helping out.
In the OP's case, I can see what happened. There was a year end promotion which their Grimco reps were using in the original negotiations. But the promotion expired while the OP dallied. Since the promotions come from Epson, not Grimco, it wasn't available any more. It's the same as when auto manufacturers offer manufacturer incentives like rebates or price reductions. They are only offered for a limited time and if you try to use the incentive after the deadline, it isn't available. The place where these particular salesmen were remiss was in not informing the OP that the promotion had a deadline.