Thank you, @
Michael Bradoyour method works*. As I said before, I know site
https://shimi.net/services/opt43/ but when you try to generate code for 2 controllers it gaves you hex string separated by "2c". In tutorial
https://youtu.be/Cwnj9mKcaFo it wasn't explained, that you have to replace excatly this part with "15". Actually, they called it "sub-code" which is a little bit confusing.
*It works on Windows Server DHCP, but on Palo Alto Networks firewall - no.