fix: formulas not working when multiple group or sessions are included

[EDsCODE]

Problem

• fixes #11895
• need to add a test
• The cause of the problem here is still inconclusive. If you run the queries with quotes around the aggregation targets "$group_0" it works but if you take them out, the query will only succeed if there's <= 1 group/session aggregation 🤔

Changes

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How did you test this code?