Replacing momentary button/switch on monitor control panel
It's hard to be sure, but it looks like the bottom board contains complete tactile switches, while the top one has dome switches.  The dome switches work by having the dome in contact with the outer pads and making contact to a center pad when pressed.  Tactile switches work by connecting (usually) two of the four leads to the other two (the main reason for having four leads is mounting stability).  They won't work as a direct replacement.  However, if you solder wires to the outer and center contacts on the top board, those could be attached to a tactile switch and would work, although mounting it mechanically will be a craft project.