In addition to the area's page ranges, the set definitions for the index must match between the two systems. In the production CV, the index schema set definition specifies
SET NAME IS IX-INDEX-SET
WITHIN AREA INDEX-AREA OFFSET 25 PERCENT FOR 100
In the test CV, the index schema set definition specifies
SET NAME IS IX-INDEX-SET
WITHIN AREA INDEX-AREA OFFSET 0 PERCENT FOR 100
This difference in the offsets specified causes the index area page range to be different between these two CVs, so that the system owned index (which is found by CALCing to the SR7) will not be found and an 0307 will be issued.
Once the test schema was modified and the test subschema generated/new copied, then the index was accessible in the test CV.
Any SYMBOLICS defined to the DMCL for this index must also match between the two systems.