Hey, Papa Pepper, You convinced me to Join steemit. Not sure what I'm doing but hey learn as you go right. As for the mice going through the fan... yeah they will most will get killed in the process so keep an eye on the fans so you can remove them ASAP it gets nasty quick and you don't want that smell seeping into the house. Living in the city we are always fighting the mouse problem and this happens to us often. I hope it works well for you! But... be sure to check the insulation closest to the floor is totally dry before you seal it back up because that's where you will have the most problems due to airflow not being able to reach it. You might even want to, if possible without damaging it, pull one side of the wet section down so it hangs and the air can get in there. Good Luck!