I created a small holder to attach the Aqara button magnetically to my desk (Secretlab Magnus). The holes take 6x3mm magnets (I used these https://www.amazon.de/dp/B0BX3VVFGX/).

I uploaded two versions:

aqara_button_holder - is a little bit wider (I would probably glue the button to it with double sided tape)
aqara_button_holder_snug_fit - is tighter and the button holds perfectly with friction