Passenger Side Electric Windows stopped working?

How did you test the breaker? Asking because that vintage GM has been known to have corrosion in the interior of the fuse boxes and the loss of power from that breaker would cause this problem. A way to check to see if power is the issue would be to pull the right front door switch out, now use a test light to see if there is battery power to the orange wire. It should have power full time. If you find nothing, then you could try jumping battery power to it through a jumper wire and see if both windows now work. If yes, then it is an issue in that relay box. As that is where the splice is that feeds both door switches.
To get to the right front switch you normally use a trim tool to release the clips and the switch comes out. They did use screws for a couple years as well. For those the door panel gets removed first. The orange wire is easy to find in the connectors.

Easy test, pull the fuse and try a jumper wire. Then a jumper for the circuit breaker. See if either one returns the windows. The orange feed goes back to the relay box and is spliced inside the box. Another test if jumping doesn't work would be to take a jumper and connect it to power, then apply that to the pins in the relay box and see if you get the windows back with power applied. If you get it that way you could use a fuse tap with the correct fuse to bypass the damaged section of the box.