Your question is Track Assumptions in a Sparse Business Case. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You're building a business case for a new operational initiative, but some of the most important inputs are incomplete or unavailable. You still need to give stakeholders a recommendation, and you want to avoid treating guesses as facts or letting assumptions drift over time.
How would you track assumptions when data is missing in a business case?