My bad. They both are in the 2nd cabinet, OS7200.
Swapped cables at boxes. Moved a phone where the status indicator wasn't working from Cab 2, Slot 2, Channel 14 to Cab 1, Slot 10, Channel 10. The light works appropriately. Then, I did an MMC 315 and swapped the extensions so the person got their appropriate extension back. Still working properly.
So, do you think I have a bad 16DLI2 card or could having the 16DLI2 in the extension cabinet (OS7200) be causing trouble?