Track campaign ROI and influence

I need campaign ROI and influence tracked for the FY26 enterprise outbound push. For the outbound Q2 campaign, set up the ROI fields and attribution model we agreed on: Primary Campaign Source with last-touch revenue attribution, and a custom influence related list that captures up to three contributing campaigns. Configure the campaign to roll up influenced opportunities into the campaign's ROI calculation and run a validation check that projected ROI matches closed-opportunity totals.

Before I tell the CRO the campaign ROI number, make the reporting easy to interpret. Surface immediate closed-won revenue and show which opportunities are primary-versus-influenced, mark any influenced opportunities with partial values, and flag opportunities missing stage history where attribution will be unreliable. Point out the three reasons the ROI could be overstated.

I calculated campaign ROI and it shows $420k influenced revenue, but finance reports only $310k tied to those deals. I used last-touch attribution and added influenced opportunities. I can’t tell if we double-counted opportunities across campaigns, misapplied the attribution model, or imported bad opportunity amounts. Which is most likely, and what are the step-by-step checks to reconcile the two numbers before I report to the VP of Sales?

Across multiple quarters leadership questions our campaign influence totals because numbers jump when someone touches an opportunity. We lose credibility and I spend hours digging each month. What habit, report, or governance change should I implement so campaign influence is stable, auditable, and defensible to finance?