No. Record Groups (RG) are created either at design-time or run-time. If the RG is created during design-time (eg; there is a RG object in the Record Group node of the Object Navigator) then you can simply look at the source of the RG to see the source of the data. If your RG is created during run-time, then you already have the SQL statement in your code because you have written PL/SQL to populate the RG, typically with the POPULATE_GROUP_WITH_QUERY built-in.
Even I am facing the similar issue. It's a client environment and we don't have access to seeded fmb. Have to create a backend validation similar to the one used in one of the fields' LOV in seeded form.
Got the hold of issue. Just enabled the trace with binds and got the query