The current implementation was mixing several types with each other, making it hard to determine what a hull and what a navmesh type is. Code has been refactored to use the new types and names introduced in commit e638cc9323c7b74279f0274591264efc53c29d4d.
The 2 fields are actually a CBitVec of 64 bits, which under the hood is split into 2 32bit unsigned integers. Type reversed from abstracted script functions 'NavMeshNode_GetBooleanData' and 'NavMeshNode_GetBooleanData'.