can I bring wild mushrooms on a flight?

That might be a job that is better for UPS or FedEx. The airline will probably think they are drugs and that might be a pain in the ass.

As for packing, if you overnighted them I’m sure that they would be fine.

But, really, I would call the airline and ask them.

isn’t it sad that in a “free society,” this question needs to be asked. Why do we let the govt run our lives??

Why do you need so many mushrooms?

read mycelium running how mushrooms might save the world

I don’t think its a good idea to take your mushrooms with you since you will have to prove some how what kind they are. Shipping is the best way.
Good luck. The world would be a better place if we all added mushrooms to our diet.

Mushrooms are neither animal nor vegetable nor mineral. So if you have your lawyer with you, you might be able to get by on the “do you have fruit or vegetables in your baggage?”. Or… do the airlines forbid “organic material”? If so, you’re dead in the water here.
Mushrooms don’t deteriorate all that fast. Don’t get them wet.