Maybe not, but "shamble" is a legit verb, and they used it appropriately.
sham·ble Pronunciation Key (shmbl)
intr.v. sham·bled, sham·bling, sham·bles
To walk in an awkward, lazy, or unsteady manner, shuffling the feet.
'Tis a rare occasion that I learn a new word. Guess I'll have to shamble off this point.