My resume contains a short internship (1 month) in a now closed startup.
Due to this I have not been able to get experience certificate from them, nor I am able to contact my former manager there. So I did not include it in the background check form for a new job.
Now I have got the offer and they have started background investigation, should I tell my to-be employer about this? Or should I just wait for their response to see if they even care about that job?
I only have a few mails of correspondence as proof of employment.