Upon entering the Miser's Hovel, there will be three Resplendent Chests that all look the same. One of these chests is 'correct', and opening it will complete the event. The other two are trapped; one will spawn an Orbiter monster affix in the room, while the other will summon waves of Shadow Vermin similar to those in the fight with Iskatu in Act IV. There is no way to know which is the correct chest: only give it a try and hope to guess right. The chests may be opened as frequently as possible; however, only the correct one contains any loot, and surviving both traps at a time may be harder. Opening an incorrect one does not fail the event: as such, a player will always eventually get the reward.
The roll of which chest is correct is completely random: there are no ways to guarantee the first-attempt bonus. However, when playing in a group, the same chest is correct for all players.
Prior to a hotfix for the 2.1.0 patch, the Miser's Will was available as a Bounty. It was removed off the list of available Bounties for Act V because the objectives listed for the event did not force the players to actually kill any monsters they encountered. This lead to said players building themselves up for movement and survival, rather than actually damaging the minions of Hell.
As of Patch 2.4 (1 February 2016) this is again an available event for the Act V Bounties (confirmed Americas Server - PC only). Further, opening the chests resulted in a wave (4-5) of Revenant Archers and Soldiers for each incorrect opening, and 4 Exorcists, one in each corner of the main room, after opening the correct chest.