Well you may think it is crazy but as it turns out you may be on the right track. I will have to do further testing to verify what made the difference.

I believe you wanted me to place extension 103 in its own extension group so that is what I did. It was in an extension group with one other extension (that was not connected).

I also varied the Call Fwd Start Time (202).

Here are the test results from a CO call:

1) Dialed 103 w/(202)=15s (default) - 4 Rings, call canceled.
2) Reached 103 via DISA AA w/(202)=15s (default) - 4 Rings, call canceled.
3) Dialed 103 w/(202)=10s (default) - 4 Rings, call canceled.
4) Reached 103 via DISA AA w/(202)=10s (default) - 4 Rings, call canceled.
5) Dialed 103 w/(202)=5s (default) - 1 Ring, call answered with Personal OGM.
6) Reached 103 via DISA AA w/(202)=5s (default) - 1 Ring, call answered with Personal OGM.

Notes:
1) While Test 5 & 6 worked the pickup time is way to short to be useful.
2) During Test 1 - 4, I noticed that after two rings on extension 103, extension 101 (Operator) started to ring too. I wonder if this is a clue to why the Personal OGM is not played.

Your idea has me thinking that my problem is a timing issue. If you can think of anything else, please let me know. Now back to the wiring closet and then further testing to try and isolate the root cause.

Rob