Ok, in this case specifically I think I know now where the problem lies. After talking with a friend of mine, sales person in Simon Tech, it seems between 2022 and 2023 they changed supplier due to the chips shortage and they started using a different Zwave version on the new buttons.
In this specific case, half of the buttons have the old version and the other half, the newer version.
As per what this guy told me, they had experienced exactly this problem that I am reporting in houses with multiple devices and a mix between old and new version.
Solution is: removing all old buttons, send it to factory and have them update it.
Anyway, thank you so much once again Bob!