Veneers fuming with fire-treated NAUF substrate

We have had problems with wood veneers that blacken/discolor when installed over fire-treated NAUF substrate, especially with light-colored wood. One theory from a fabricator is that the combination of chemicals causes fuming because the binder in the substrate reacts with the ammonium poly phospate fire rating agent and off-gases ammonia. Fabricators are not willing to warrant against discoloration or even delamination for any species of veneer, so our interiors group will not specify NAUF for veneers that need to be fire-treated. We've heard that one possible solution is Duraflake FR particle board, which meets all of the IEQ 4.4 LEED point criteria and meets the class rating. Another suggestion was not to stack panels during staging. What is your experience?