User Deny - How to use it in formula

Question:
Is there an option to pull "Realm Status" to my application to notify user to not select this person as Approver?

Background:

I have app which supports process which is run only from time to time.

It happen that user goes on Deny List, and when somebody select him as approver, they does not receive mail notification. I cannot make this app EOTI.

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Adam Krzyzanek
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