Ride together, die together achievement is bugged

Achievment does not trigger when playing Boom Master Flark which summons 4 identical deathrattle minions.

It falls under this criteria wording:

Hey, even with the right wording its still bugged…

example: i used toxic reinforcements, i got 3 lepper gnomes, i finished the round (with all 3 deathrattle lepper gnomes alive) and still get no acm, wound be nice if u chek your acm before giving false answers.
thx and i hope u can sove the bug

Well, have you done it in Ranked or Casual? It seems these XP-rewarding achievements do not update in Casual.
I have used Toxic Reinforcements successfully in Standard Ranked