Hiding a form field using a fomula

It sounds like what you are asking can be done with a Form Rule.  Why are you not using the Form Rules?  You will just have to set up the Rule's Condition multiple times for each value.

Multiple Conditions
when EstimateStatus is not equal to "Closed - Not Denied"
when EstimateStatus is not equal to "Closed - See estimate notes"
show EstimateFollowUpDate

Otherwise, it is easy to do the same thing in a Formula - Date or Formula - Text field using the If() function.  Just pick Text or Date depending on how you are using that Field.  You will need to do something like this:

var Text splitValue = "; ";
var TextList valuesNotAllowed = Split("Closed - Not Denied; Closed - See estimate notes; Closed - Unable to authorize", $splitValue);
var Bool notAllowed = Contains($valuesNotAllowed, [Estimate Status]);

If($notAllowed, "", [estimate follow up date])

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Joel Hickok
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