[confirm]Nether Traitor triggers more than 1-casts top card

Describe the Bug:
1) When Nether Traitor dies, its triggered ability triggers.
2) The triggered ability prompts Nether Traitor's owner to pay
.
Which card did behave improperly ?
Nether Traitor
Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
BfZv2, Gauntlet
What exactly should be the correct behavior/interaction ?
Nether Traitor's triggered ability only triggers when another creature is put into Traitor's owner's graveyard from the battlefield while Traitor is in that graveyard.
The triggered ability prompts Nether Traitor's owner to pay
.
Are any other cards possibly affected by this bug ?
-
2) The triggered ability prompts Nether Traitor's owner to pay

Which card did behave improperly ?
Nether Traitor
Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
BfZv2, Gauntlet
What exactly should be the correct behavior/interaction ?
Nether Traitor's triggered ability only triggers when another creature is put into Traitor's owner's graveyard from the battlefield while Traitor is in that graveyard.
The triggered ability prompts Nether Traitor's owner to pay

Are any other cards possibly affected by this bug ?
-