RMA has released Manager's Bulletin MGR-17-015 that does confirm that quality adjustments for fumonisin will be for samples 2.1 ppm or above. This confirms what was discussed at the Dumas meeting with Matt Mitchell from RMA stating that the LAM was incorrect.
The Manager's Bulletin also has a link to the Office of the Texas State Chemist for a list of approved elevators to do fumonisin testing. Currently, Dumas Coop is the only elevator listed. On October 10, I confirmed that Servi-Tech Labs in Amarillo is now also certified to do fumonisin tests.
Finally, as suspected, RMA is planning on putting a fumonisin discount table in the Special Provisions of Insurance (SPOI) for 2018. This would eliminate the default 0.500 DF for unsold grain or grain in farm storage (including grain bags).
Link to the Manager's Bulletin:
https://www.rma.usda.gov/bulletins/managers/2017/mgr-17-015.pdf