Anyone know guys who have met this requirement and how they went about it

I have a minimum of 90 days experience performing wildland fire suppression duties as a member of an organized fire suppression crew or comparable unit that utilized knowledge of fire suppression, containment or control techniques and practices under various conditions.

Smoke Jumping!

Sounds like they want you to work a season on a wildfire crew...not too hard to get into that.

I looked into this at one point (many a job Cubdriver looketh into). You can have the 90 days working for any non-aviation county fire department in the USA, no problem, anyone who will hire you as a shovel grunt or dozer driver might fulfill this simple requirement. But be careful about it- do not a position if the department in question does not primarily do wildfire or forest fire suppression & control. To test the theory- imagine the US Forestry Service hiring manager calls your local FD and asks exactly what it is you all do there. "Put out apartment fires in downtown Phoenix" - is not the right answer. Make sure they do a lot of forest fire or wildfire suppression work.

However if you have that 90 days and the other mins which are not steep- you could be quite competitive. You will not get rich working for the government. But you will never get laid off, you will enjoy good benefits, and you will almost never get pushed too hard.

Apparently, I've been doing something wrong in my work for Uncle Sam.