Background Checks - Very Short-Term Jobs

For those familiar with consulting recruiting/background checks, I’m curious how MBB, Big 4, and boutique consulting firms handle employment verification.

I have two jobs where I worked for only a couple of days and was paid, as well as a situation where I was let go. None of these positions are relevant to my consulting experience, so I did not include them on my résumé.

If I receive a consulting offer, would a standard background check be able to identify employment that lasted only 1–3 days, even if I don’t list those employers on my résumé?

Would especially appreciate responses from anyone who has gone through consulting background checks or works in recruiting/HR.