By the way...it might be a good thing that you ordered two. Recently, for the first time I actually replaced one with a BIN cheap ferrule on eBay, as I had just received a tube without one in a parts lot. The pin hole placement is kind of crucial, if they aren't in the exact spot, you will have either a little too much or too little gas tube to fit nicely....and handguard length comes into play again.
It sounds like your gas tube might be a little shorter than the norm, which one of mine is like that...and fortunately with my mismatched ferrules, I was able to swap parts out between two tubes and get a favorable result. Your new ferrule also might allow for the ventilated guard to work. You may want to hang on to that until it arrives...rather than take a loss on it.
just saw your post about the shipping, whew...that is a relief!