I think it may have just been a processing time issue...I ran for 2 hrs (I know, I know) and no progress, so then I tried mixing up the order a bit and got the load to work relatively quickly with the following script:
text("TDLINX Code") as "TDLINX Code",
Capitalize("Marque Description") as "Marque Description",
FROM [lib://Master Data Source Location (ws-na_singhvi)/MH SF PLACEMENT.QVD]
LOAD "TDLINX Code",Concat("Placement Type",',') as Placements Resident PlacementsTable Group By "TDLINX Code";
left join (MainTable)
Drop table PlacementsTable;
The concatenation is pulling in far more values than I anticipated, but I suppose that is something else entirely. Thanks for the help Petter, I will mark this as closed.