A couple of things.
First, if your trip is only two weeks, you can probably forget about stretching and drying. You would no more than get started, then you'd have to stop. It could work if you had a really good facility.
I don't think ice or dry ice would be practical either. You couldn't keep pelts "on ice" for a week or more, they would spoil. Tim likened this to keeping them in the refrigerator, and I agree. You can keep a pelt in the refrigerator only a few days.
The other thing is capacity. How are you going to get a "cooler" big enough to hold this project? And enough "ice" to keep it going?
I think the freezer is really the best option
Endeavor to persevere.