Not sure what your referring to, there doesn't appear to be anything like a red object in Doormans hallway. May be a texture bug, try verifying game cache.
You’re most likely testing it in the sandbox or practice range or whatever it’s called, which has q big red sphere out of bounds that happens to be placed in a way that it’s visible in Doorman’s ult.
So this doesn’t happen on the actual map but I suppose it is still something to fix.
Similarly, in Doorman’s ult on the hub/lobby map, you can see part of the exterior of a building.