Self Referencing Reactive Record Field Not respecting OR Criterion

I have a Screen Flow API 60 embracing full reactivity. I have a requirement where a user can click Save or Finish while filling out a Form. If they leave the Sample Code empty, Finish is permitted (and no form information is retained), if they populate the Sample Code, all other validations / requiredness attributes must fire.

Since this org is

1. using Experience Cloud,
2. has 3 significantly different types of forms where the same fields have different values (using 3 Record Types) and
3. has complicated field dependencies (using stacked field dependencies 1-3 layers deep) and
4. has complicated translation requirements (8+ languages)

I have opted to use sObject records displaying the conditionally dependent fields using standard Screen Flow Record Variable Fields and am making the fields required at the field level with n/a options set with Before Save Flows to ensure no impact when the value is not needed. (Where page layout requiredness doesn't care if there is no dependent value, field level requiredness does, so this is annoyingly required until Salesforce permits us to set the field value requiredness of sObject Record Variable fields in Flow Screens).

Setting Sample Code with the following visibility does not seem to respect condition 1 and the value hides when the button is clicked even though there is value in the field (as tested by using display text and testing condition 1 and 2 separately) 1 OR 2

1. sObject.Sample_Code__c is null FALSE
2. ButtonBar.value is null TRUE

How can I maintain the current build / complexities and get expected reactivity?

These options did not work in my tests:

• Formula Boolean HasSampleCode !ISBLANK(sObject.Sample_Code__c) returned FALSE every time (i.e., did not respond to any change to sObject.Sample_Code__c)
• Formula Text SampleCode sObject.Sample_Code__c returned null every time (i.e., did not respond to any change to sObject.Sample_Code__c)