Vermicompost is the best solution for this situation. If you run the bin correctly, there shouldn't be issues with rodents. If there are already rodents present, you can use lids to cover the bin and seal it up, so that the only access is 1/2" holes in the bottom of the bin. I used the directions on Vcompost.com and I keep it in my garage without any issues.

Here is a link that might be useful: Vermicompost Guide

If you could set up a few bins indoors that would be an ideal situation. Plus you could feed steadily year-round.

It's been my understanding that the main reason meat is not recommended for worm bins, is because of the attraction of rats and other rodents. So even if you had to set up your bin outside, don't add meat to the bins and make sure the bottom holes are too small for rats to enter.

Just my thoughts, anyway