STRUCTURE interprets pop ID as locus
Hmmmm .... you don't actually need pop ID to work for Structure, providing their are no logical errors (you get a wrong answer). The bit that must work is the a priori number of populations in the data set. You are then going to manually (or via a script) feed a range of a priori values into Structure, run each and plot the likelihood. Where the likelihood plateaus thats the number of populations contained within your data. This is the key output of Structure.
Personally, I would perform a Structure run on the test data and remove the pop ID column and check the answers (likelihood -lnL) are identical. Thereafter use an approach such as $F_{ST}$ to interrogate the exact members of each population delineation.

I think your test will work .... The only thing I can think of is the header comprises a space, This format just needs checking against the test data.