OK - There ARE three blades per switch, but only two wires. The blades with the wires are "normally open". This is one problem you need to do as the game is totally confused as the coin switch is NO and is a momentary switch. Gap that switch.

The second coin switch is disabled and it looks like the wire has simply been jumpered to the working side for continuity.

I do recall this exact issue with a Space Mission whereby the coin switch arm would get caught on the bottom of its travel, thus closing the switch and a game would never start as a result.