You are saying as a fact that the seller gains in ranking when items are purchased and then cancelled, and are assuming that this was the seller's intention?
The email actually does not read like a scam. It reads like a price mistake or unintended promo which the seller wants to cancel without hurting his metrics. The seller does not seem to have gained from the process. (Whether anyone will actually lose their job or starve to death is irrelevant.)
Chalking it up to "many potential scams which I am not aware of" doesn't count for much.
People make mistakes.
My sincere opinion is that it reads exactly like a scam. An email that did not read like a scam would have said something like hi this is company x we recently posted a coupon to Amazon not realizing that we also had a secondary discount and this mistake has been very costly for our company. We would appreciate if you could cancel your order.
While I would be suspicious I think I would feel inclined to believe such an email. However let's think about what was written in this email. This email takes a different approach. Rather than asking you to understand that a company made a mistake and it might cost the money it instead tries to appeal to your sense of compassion and guilt.
That's a really weird thing for a company to put out.
Hi my name is Anna and I'm going to lose my job if you don't cancel your order? That literally sounds straight out of the playbook of every scammer in india. Hi ma'am I made a huge mistake and if you don't send money to this email address I'm going to lose my job!
Think about it isn't that a really weird appeal to make. Imagine if this intern named Anna and let's not focus too much on why a Chinese intern is named Anna, but that's fine, let's assume that it would possibly be true. Anna has made a terrible mistake. Do you think that the right response is for the company to have Anna send out a very personalized email about how difficult her life is and appeal to your sense of compassion and try and guilt you into canceling your order? I apologize but it sounds exactly like a scam. It's bizarre and creepy that you think that that sounds normal.
Try and imagine you own the company that sold things on Amazon and a guy who works for your company came and told you hey remember how yesterday you told me I should set up a sale, well it screwed it up and we're losing lots of money. There's lots of things you can do, you could fire the guy, you can email the customers asking them to cancel their orders, you can tell the guy he has to email customers explaining that a mistake was made, I could hear all or some of those things being done. Do you think you would allow him to send out an email saying hi I work for this company and they threatened me that they would take away my livelihood and hurt my family if I didn't correct this error? You would allow such an email to be sent out representing your company?
I might be cold and heartless but it sure does sound exactly like a scam