1N4148.

0.047 or 0.05ufd any voltage as the matrix is running at only 5VDC

Yes, one lug on the switch is just used as a solder joint to put the diode in series with the switch. Cap is across the switch contacts.

Look closer. The third solder lug is isolated from all the blades. It is just used as a solder point. Third center blade is actually electrically connected to tge other blade (shorter) blade it should be laying against. It is used to stabilize the shorter point blade so it can maintain good pressure when the other blade comes in contact.

Make sure none of these in between blades are not crossing over to the opposing blade (switch always closed)

Otherwise, check for a broken wire at any other switch that shares those wire colors (even ones that ARE working)

If you get 01 in switch test, one or more of those switches is stuck closed. Unsolder wires from one or all three until you have a zero in switch test (or blank?)

Both wires of the same color. One is the incoming and the other the outgoing as the wire chains its way down the playfield.

Unless you have something physically grounding out to a switch or wire, removing one like colored pair from each switch is enough to take it out of the circuit.

Those caps fail. They can short out.

When having weird switch issues, about the first thing to do was clip one lead of the cap right next to the lug.

If the problem went away, you found the bad cap, if not, you could always solder the clipped lead back on.

But now, due to their age, all should be replaced with new ones.

I use the leads full length and wrap them around a small allen wrench to form two shock absorber springs so the leads don't break off from vibration (another common problem back in the day).

Good point! The minute someone takes anything but a business card or cotton swab to a gold flashed SS switch point, it is basically destroyed and will require constant attention.