In New 52 Suicide Squad #29, Amanda Waller makes use of a portal nicknamed "The Toilet" as a plan B to bring a Thinker-controlled O.M.A.C down.
There is a hint that it may lead to "some other universe", but nothing specific at this time.
At the end of this issue, O.M.A.C and King Shark both fall into the Toilet. I don't remember seeing King Shark as a Task Force X member in New Suicide Squad (haven't read Suicide Squad Rebirth yet), and I don't know if O.M.A.C reappeared in some other series after that.
Do we know where this portal leads?
Have O.M.A.C. or King Shark appeared since then (in New 52 or Rebirth titles), perhaps providing some hint of where they went?