Let's use some logic.
If accounts had different IP-s, different computers OR computer accounts, different banking accounts, different names, addresses....No way Amazon could link them.
Even if the same type of products were sold, still impossible.
I am guessing you used the same wifi connection from different accounts and IPs and got burnt.
Allow me to share with you my experience.
Amazon sales bring my family good money and everyday business. We sell different products, however customers can destroy you by bad feedback or accusations of selling non authentic products.
You need to have several amazon accounts, I mean COMPLETELY separated, if this is a good source of money.
Open (gradually) few LLC-s, with different addresses, different bank accounts.
Use different PC-s, different routers and different WiFi connections if needed.
Each account must sell completely different group of items, never sell identical items on from different accounts. Their system can "notice" pattern, same type of photos, etc.
Only this way you can completely secure yourself. Yes, it can be costly, but to establish a new business can be about $300-400 including your router, or
VPN (annual membership around$100). Get a cheap PC... If you are confident that you are selling a good product and your sales are going to be fine, this investment is worthy. Don't give up, try harder and do NOT cut corners.