Does real wood cladding actually meet fire code on commercial buildings? Keep getting told 'no' by GCs.

Designing a 4-story boutique hotel and the owner wants real wood exterior (not wood-look fiber cement). Every GC we've talked to says it won't pass fire code. But I see wood-clad commercial buildings going up everywhere, surely there's a path? Specifically: IBC 2021, Type IIIA construction, jurisdiction is pretty strict. What species meet the flame spread requirements without chemical treatment? And where do you even get fire test documentation for specific wood species?