Auto glass has 2 layers and thus some structural support for the outer layer but the inner layer. Your plastic window in single layered and the common means of repairing Plexiglas is a melting bond. that wold likely leave distortion in the window.
I have replaced one of the curved Plexiglas windows on my trailer by just buying the material at a plastic supply house.
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles