Plant them. You have nothing to lose. They won't keep once they're sprouting.

Unheated garage? You might very well have what are more or less "pre-cooled" bulbs that will do ok for you in pots. I would guess you should get some bloom. Any is better than a total waste and if the pots look ratty, tulips make very nice cut flowers.

Crazy cut-flower tip for tulips: add one tablespoon +/- of gin to the vase water, This helps tulips last longer and helps prevent stem stretch floppiness. (Tulips keep extending their stems once in vase.) I worked as a floral designer for 12 years and this is what we did for tulips...

(fun) Sauced tulips...do you drink the water after you throw the tulips out? (yeah, I've heard that tip before...though haven't actually ever cut my tulips to use it).