I understand you are having troubles setting up daisy chain in your HP* computer. I will be more than glad to assist you.
I was checking the manual of the monitor, but it does not mention anything related to either daisy chain or MST. Have you contacted HP* in order to make sure the monitor supports daisy chain?
Usually there is a special setting that needs to be set in the monitor to enable daisy chain option. Even though there are two Displayport* ports on the back of the monitor there is a chance daisy chain might not be supported.
HP* contact information https://support.hp.com/us-en/contact-hp
Monitor manuals https://support.hp.com/us-en/product/hp-z24s-23.8-inch-ips-uhd-display/7155481/manuals
Comparing different HP monitors specs it does not mention specifically the ability to daisy chain.
It supports DP 1.2 and I was under the impression that was enough.
I still haven't tried different monitors with same machine or different machine with same monitor,
but it seems the monitor is indeed the problem.
thank you for your help!