There is a bug with event keys. (Xbox One)
If you purchase 50 event keys (using keys, I have not tried with gems) the rewards screen shows you getting WAY MORE than 50 troops.
However, the bug is visual only, you don’t actually get the extra troops. I got extremely excited in 50 chests to have received 5 Glaycion and 3 Kingbloodhammer, but when I went to my troop collection I didn’t have that many.