i reckon you should be lvl 58-60 because you get xp for that quest and i dont see the reason getting xp if your already maxed out :( :( :( :(
The reason they give xp is to give new players the xp after the level cap increases.
Briskbreeze Tower has always given xp, but when it was first released all the level 50 players did not receive it. Now, new players that attempt before level 60 will get xp. Same scenario for Helephant Tower and Waterworks.