Bypass button info with bool values…
If 1 is pressed set button_1 true
If 2 is pressed set button_2 true
If 3 is pressed set button_3 true
if 1 is released set button_1 false
if 2 is released set button_2 false
if 3 is released set button_3 false
if button_1 & button_2 & button_3 then do your stuff
And… it's done.