Nightingale PTR Portal
After I noticed the Pepys box missing from Boss Rush, I checked with the PTR chat to see if anybody else had theirs missing as well. While checking on that, we noticed that there is no "Reset Realm" option for the Boss Rush portal. It's there for other portal types - just not the boss rush.
Including screenshots of both with portal open and with portal closed.
We removed these options deliberately as boss rush is reset each time you enter or die, is there a reason you wanted to use the reset on a boss rush realm?