How are you connecting the data you collect (after a learner finishes courses, etc. ) to a "Return on investment" for your company?

What Tom said. 

Another approach is to focus on business success metrics instead of ROI and perform an impact mapping exercise.

Step 1: Identify with the business unit their 3 big MEASURABLE metrics that define/determine success and are stated in a smart goal format. For example, a support org might have something like "Improve Customer Experience [CSAT] from xx% to xx% by December 31, 2022. (x% per Fiscal Quarter).

Step 2: Identify what is required to achieve this goal and bucket by People | Process | Tools. Some organizations will perform this step by looking at top performers to identify which tools they use and how they use them, what their process or processes are &/or how they organize themselves, and lastly, what their interpersonal or soft skill "inventory" looks like. This gives you your learning topics.

Step 3: create actionable objectives for the above topics and begin course development. I like to use Cathy Moore's Action Mapping process for this.

Voila! You've now tied your courses directly to company results and while you cannot state that you are the only reason a metric moves, you can infer that you are having an impact.  You can also seek to measure if doing the above improves the quality of your training program by demonstrating a reduction in the time that it takes to move a high potential employee to a high performing one.

Companies tend to like ROI because it is a results measure... but so is reducing time to high performance. Both measures show training value which is ultimately what the company is interested in.