The fan is pretty loud on these things so yeah they do drown out the turbo a bit when the engine is warmer. If you lay down the power you can definitely hear it with the radio off. Our trucks do have active noise canceling and that bs fake engine noise in the speakers so that may be hurting...
Check out american trucks they have not only lots of parts and stuff but also a catalogue of builds and stuff where you can see what things ppl have added on, does a great job giving a preview of what it would look like
take it elsewhere, also have you spoke to the actual manager there calling ford is a good step but doesn't do a lot I would follow up with ford themselves again as well as with the manager there also bad reviews usually help to spur action