Dashboard EpiCombo filter not working

I am modifying a dashboard that already has a customized tracker view. Currently Vendor.Name is not set up in the tracker view properties (prompt = null, condition = null), but I would like to add an EpiCombo to show the list of vendor names to filter the query by.

I added an EpiCombo field in Customize Tracker View with the following parameters:

DashboardCondition = equals
DashboardHonorNull = false
DashboardPrompt = true

DisplayMember = Name
EpiBOName = ERP:BO:Vendor

EpiTableName = VendorList

ValueMember = VendorNum

IsTrackerQueryControl = True
QueryColumn = Vendor_Name

If I have nothing in the combo box, I will get all results. If I filter by a vendor name that I know has records, I get nothing. I tried setting up a new dashboard that had prompt and condition set to true for Vendor.Name, but still nothing. Is there an issue because it might be using Vendor.Num to actually do the filtering (ValueMember above)?

Thank you in advance.

may i ask why doing it this way, if i were you, I would have just added the VenderNum or Name to the relevant table on the BAQ and apply a criteria to show the active ones only, then use this new added column in the Std CustomTracker filter fields

We would like to filter by vendor name, without having to type it in. The employees might not know the exact name of the vendor, or what letters the name starts with. They can easily pick it out of a list though.