Some Program Letters for DEDP learners are not getting created

[annagav]

Couple of learners were missing their Program Letter even though they passed the program and the progress widget is showing that they passed.
Related tickets: https://github.com/mitodl/hq/issues/1441

[pdpinch]

What’s involved with re-enabling DEDP letters in MicroMasters? What would it take to move this function to mitxonline.mit.edu ?