How to access person habits via fast formula, specifically disability status

Summary:

Need a Default Enrollment fast formula to fetch the disability status for a dependent

Content (required):

Working on a default enrollment fast formula that defaults the employee in the next lower level of coverage, for when a dependent ages out. However, for dependents that are disabled, yet over age, they are still eligible, so they should not be de-enrolled. In my fast formula, I need to fetch the disability status from the person habits table.

Note that I've used the BEN_PHB_DISABILITY_STATUS database item from the BEN_PER_LE_HABITS_COV_F user entity to no avail.