I've been in the same boat as you, waiting for the price of the Magic Trackpad 2 to drop.
I really don't think it's had any significant discounts since its release in 2015, and wouldn't count on a price drop anytime in the near future.
For a $6 difference, I'd trust in the higher quality of Apple's customer service, and buy it directly from there. Better yet, you can request a price match at the Apple Store.