i think that gadgetron was used to be called galactron, but then they changed it
but was the PAL version not released after the US version? (I truly don't know, I just assume this because it has a few fixes the US version does not)
I just played my PAL Platinum game today and found an old completed save and well guess what:
Sorry it's a bad pic ^^'
I'm goning to check the collection.
EDIT: Sadly, the collection has GADGETRON not GALACTRON.
Whoa! Very interesting!… Maybe Insomniac did this? dunno.. But that is very odd! I might have to do a speed-run!
Hmm thats strange my says galactron too 
xD the easter egg were you keep jumping over the lady at the hoverboard race