My friends I have suffered this corrosion for my 2015 Gli too, and I cleaned it at home and next I use to keep it covered when parked at work and home.
Yes for the quality of these emblems is pathetic, for my car the corrosion popped out the 4th month after purchase.
Our local manufactures, more they localize the cosmetics worse the assembling results, plus the mother companies like Toyota/Suzuki/Honda do not care for what these licenced companies do, they should keep complete check to keep the standards alive at every off-shore factory
My 2006 cultus till 2014 did not showed the rust signs, but this 1year old corolla did.