I have 2 three way switches controlling 2 lights, one on house one on garage. I therefore have 2 buried 2 conductor cables between house and garage. One conductor has gone bad underground and would be very difficult to dig up and repair. There is a wire from another circuit passing through the house switch box so I could connect the neutral wire from the light at the house to the neutral from the other circuit and then have the neutral from house to garage to use as a traveler replacing the broken wire. Will this work?

Please do not do this... it is not good practice nor does the electrical code allow it.
Creative wiring like this can be a land mine for the next guy to find...