Feeling Anxious About Background Check: Should I Disclose My Brief Abscondment?

I absconded from a previous employer three years ago in a rush due to a COVID emergency. It was a mistake. However, when I contacted my former employer, they informed me that since no salary was given for that period, providing a relieving letter might pose a compliance issue (they did mention the exit date on my EPF account). Nonetheless, they agreed to send me an email regarding my relieving.

I am currently working at a Big 4 firm after completing my master's degree. Since my previous employment lasted only a week, I did not include it in my CV or company records. Should I disclose this information to my new employer along with the email screenshot, considering that my background verification will be conducted soon?

I am feeling quite anxious. Could this situation jeopardize my career?

It is always better to start with a clean slate rather than surprising the employer. You will know the employer's response immediately, and this would definitely be helpful.