[mothered]

when amazon open an investigation will they check if your credit /debit card was used on any other accounts?

It depends on the nature of the Investigation, and whether It warrants checking transaction records.

If so, they will.

Ok thank you , I have decided I will delete the account after the SE, that way they delete transaction details as well

I believe this Is a wise choice.

It's good practice to remove all Identifiable details, no matter how small It may be.