Muscle mass burns more calories at rest but the effect is very slight. Eating back any calories from exercise will absolutely outweigh any slight change in base total energy expenditure.
Focus first of what you eat, then sustainable exercise, then specific tuning of both.
Being an IT auditor is largely just working with spreadsheets, leverage your prior knowledge, and you are never on the hook for a feature release. If you are good at writing reports, spreadsheets, and meetings, you might give that a look.