SharePoint 2010 Gotcha: Associated ECT Column Does Not Show Up in Filter Choices

I have a relational table in SQL Server that I access in SharePoint 2010 as an External Content Type. The table, disks, has an FK (serverID) that is associated with a PK in another table, servers, via an Association Operation. Once I create a list and add it to a webpage, I am unable to select the serverID column or its associated lookup column serverName.

After two days of troubleshooting and research, I decided to just stuff the code into the web part and surprisingly enough, it worked! Not only that, once I forced the query in the code, the column magically appeared in the Field Names drop down in the Filter Criteria. Wanna show SharePoint who's boss? Replace in your web part's code with something like this: {ServerID}
The above is what I used to filter the results using ServerID in the querystring and it worked just as expected.