I've run into an issue where the WixDataQuery.include() function appears to randomly stop working. The simplified version of what seems to happen is that if I create a new multi-instance Reference column in a custom database to another and add data to them, .include() will work for a couple or few queries, but then it just entirely stops including the referenced column in the resulting items, even though I can see the items there in the database referenced correctly. It doesn't throw errors and I can see the inclusion in the WixDataQueryResult object, but the actual items don't have the referenced objects.
Does this sound familiar to anyone else? I can try to provide code samples but the code I have is almost the exact same as what's in the API reference.