Require Field Updates based on another field changing

I have used Quick Base to build a client portal for customers to view their service incidents with our company and I want to build in a mechanic where if a service case status changes then a portal update is required for the agent.  I am not finding a way through a Dynamic rule to force a field to be required based on a specific field change.  Status is a Text-Multiple Choice field.  

Has anyone achieved this?  Am I missing something basic?

Also, I need this to happen on only specific tickets for portal accounts/customer so the Dynamic rule would be like this:

If Status Changes
AND
Client = XXXXXXX
Then 
Require Portal Update


Any help is appreciated.

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Joshua Case
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