I need to delete my old Account

Hi everyone, I have an old Instagram account that I haven't used in over 10 years. Unfortunately, there are posts on it that I need to have deleted for professional reasons. My employer works in the security sector and found the account during a background check. I no longer have the login credentials and I can't access the email address linked to the account either. I tried to verify my identity via video selfie, but it didn't work. If anyone knows a way to either log back in or get the account or individual posts deleted, I would be incredibly grateful.