Keep in mind that "manual transmission" does NOT automatically mean towable!
Many manual transmissions are splash lubricated. That "splash" comes from the cluster gear in the bottom of the transmission. That gear is turned by the input shaft ONLY. When the input shaft is not spinning, the cluster gear is just laying there. All of the bearing and seals on the upper part of the transmission are getting no lubrication. If the vehicle is towed, eventually something will self-destruct due to lack of lube. Yes, it may take a while, and you might only notice more noise than usual while driving the vehicle, but it WILL eventually break, and it WILL be expensive.
good luck.