DynamicQueryAdapter and global BAQs


I'm working on a customization to return the quantities for a Part
in the other companies of the same database.
I have a nice Cross-Company BAQ that returns from PartWhse the quantities
I need, filtering out the ones from the current company.
I'm using DynamicQueryAdapter in the customization with
ExecuteByIDParametrized returning the rows. It works fine.

The problem is that when I make the BAQ global - no other changes -
suddenly the number of rows falls to zero for the same part.
It's finding the BAQ but not returning any rows.
Has anybody ever heard of a limitation in DynamicQueryAdapter
about using global BAQs ?

I'm on Epicor 9.05.607B and SQL Server, using Multi-Company Direct for synchronization.

Thank you and have a nice day,