What legislation is your business group operating under?
Possibly the API is using hr_leg_lookups, which is also a view on the base FND_LOOKUP_VALUES table; similar to hr_lookups (hr/payroll application ids) but further filtered by comparison of tag values on each row with the legislation code of your business group. Do the leaving reasons have any tag values on them? e.g. +JP or -GB.
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CT
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