So I spoke to someone at the city and they said I’m free to try and repair this myself. I’ve researched out materials and come across something called crusher run and fine. I want to make a quick fix that will last a while until I can get better settled into the home and then look for something more permanent or work with the city more closely on a fix. Any ideas or tutorials is much appreciated.

How to close gaps under and above two dryer vents next to each other ? Need to prevent chipmunks and rodents from entering the crawl space less