You are all looking in the wrong direction with faulty equipment, making the wrong conclusions.

The Y dwarfs are in our sun's neighborhood, from approximately nine to 40 light-years away. The Y dwarf approximately nine light-years away, WISE 1541-2250, may become the seventh closest star system, bumping Ross 154 back to eighth. By comparison, the star closest to our solar system, Proxima Centauri, is about four light-years away.

"Finding brown dwarfs near our sun is like discovering there's a hidden house on your block that you didn't know about," says Michael Cushing, a WISE team member at JPL. "It's thrilling to me to know we've got neighbors out there yet to be discovered. With WISE, we may even find a brown dwarf closer to us than our closest known star."

It is still impossible we might have one 1-3 light years away hiding in the Oort cloud?

If yes, you need a serious reality check.

[link to science.nasa.gov]

[link to spaceobs.org]