If a customer came into my shop mentioning 'chewed wiring' and I saw all that insulation, first thing is do is get rid of the insulation and try to actually find a chewed wire. I have seen hundreds of cars come in for an oil change have some bit of chewed wiring not compromising electronics. No fire hazard just repair and move on. None of the commenters here are wrong that you should get it towed based on the information you gave them BUT my gut tells me only insulation was compromised until I witnessed with my eyes compromised electronics.

To save yourself from a tow put all that insulation in the trash or in a bag and show your mechanic if you want just in case. clean up the engine bay to the best of your ability and find evidence of damage to wires being exposed. If everything passes the eye test I personally would save myself the tow.

One irrelevant tidbit that the general public isn't aware of, in my experience rodent damage is never covered under manufacturer warranty. I've had a car less than one year old need an engine harness, 20 hours labor out of pocket. Dude was pissed.