Shiny Coin spawned too many chests on the map

sizzlingmario4

I used a Shiny Coin in this match and it should have added 2 extra chests (for 5 total) but there were actually 9 chests on the map (4 more than there should have been). You can see 7 of them in the picture which is already more than there should be.

I was the only one to bring a chest-related offering and the killer was not using Hoarder.