Hirelings
Standard Hirelings (p.28) 
| The vanilla DMG pay tables for standard hirelings are a useful reference point but not a formula. Compensation in Oath-Bound is customary and reasonable — reflecting prevailing practice for the role and locality, and negotiated against that backdrop rather than read from a table. The GM uses the tables for calibration; the actual arrangement is a gameplay event. |
The vanilla pay scales apply as a baseline. Local conditions, scarcity of the skill, and the nature of the work may all adjust the figure in either direction.
Expert Hirelings (p.29) 
| The vanilla DMG expert hireling categories include races, classes, armor types, and weapon specializations that are not present in the Oath-Bound setting. Entries for absent races, classes that do not exist in Oath-Bound, and equipment categories outside the setting’s scope do not apply. |
The customary and reasonable principle applies here as it does for standard hirelings. Expert hireling retention is a gameplay event — a function of relationship, obligation, and the terms of whatever bond of service exists — not a table determination.