I had a similar issue with "Entries" not responding to dictionary blocks as expected.
In the end I treated "Entries" as a string, and used text manipulation blocks to get at the string(list) I was after, and converted it back to an AI2 list.
Yes, the return value from GetEntries is a valid dictionary, you can get values and keys from it correctly. But when any value is a list or dictionary then those values are returned as string and the list is not recognized as a list.