TFDMemTable after CloneCursor returns no records

Calling CloneCursor from an TFDMemTable on a TFDQuery usually works, however I have one case where the TFDQuery has a single record, but after cloning it, there are no records in the TFDMemTable.

Has anyone else experienced this?  Note: there are a few special things about the TFDQuery:

1. it is Cached
2. it is a detail query
3. it is also a master query to a different dataset
4. the name of the FDQuery has an unusual character in it: #20 (no, that's not supposed to be hexadecimal)

Also note: the CloneCopy uses default parameters, only passing in the source dataset.