The option of using the Data Dictionary dump and load is viable, provided you follow these rules:
Multi-thread both the dump and the load. Generally, you should add sessions on both the dump and load until you cause a bottleneck on the system.
Use all of the disks on the system evenly to achieve maximum throughput. For example, you might want to make use of your BI disks because they will be idle during the dump portion of the process.
Leave the indexes enabled during reload. This does not make for efficient indexes due to index splits during the load process, but since the indexes are built at the same time the data is loaded, you can take advantage of the multi-threaded nature of OpenEdge. The indexes can be reorganized later through an index compress.
Multi-thread both the dump and the load. Generally, you should add sessions on both the dump and load until you cause a bottleneck on the system.