Okay–after some extensive testing, I’m convinced this is a bug.
I can get it to work when the ‘Like’ field is using a UD table like UD103.Key1, but not from an Erp table. I tried your BAQ, a simple Order BAQ I made, and a simple PO BAQ that I made. All of them return undefined.
Here’s the interesting bit.
When it’s a UD table, the multiple search results are populated in ErpSearchResults with the one you select in searchResult (Proper BAQ Column names and all).
However, for the Erp tables, it shows the proper search results in ErpSearchResults, but when you select one, the row in searchResult is not correct. It’s not from the BAQ–it’s from the SalesOrderSvc.
And to touch on your earlier point about the GetList being called after the ExecuteBaq, when I do the UD103 one, it shows the UD103List table which does not include my BAQ columns, but that does not seem to matter as shown by the prior screenshots.
Long story short–you should submit this to support.