SCP-049 can easily reach the player in his tunnels, because no objet that can block him. But, once he has taken the elevator, he get blocked by anything (I think the normals rooms are too thin for his pathfinding compared to his tunnels , that why he get blocked.) I've saw him walking to a wall, under the Gas catwalk, I've encounter him later in the same room, but he was now walking on the bridge, blocked by the guard-rail and the wall. For example, you can see him blocked by a wall in this video : http://youtu.be/4BVLsUkSWFc?t=13m4s

I'll try to find other videos showing the bug.

Even in the tunnels he also has some pathfinding issues, it seems, as shown here: http://youtu.be/YzFUvG8VsaA?t=7m22s (this video also shows the bug that seems to have been just recently fixed where 049 and 049-2 do not turn the player into a zombie)

He gets stuck in the little room that opens up (around 7:27-55, as you can kind of make out his walking sounds and everything but he's stuck in the room) and he even gets stuck in his actual chamber (where the switch is) at about 9:26.

He keeps teleporting to me! In the room with SCP 939, 049 actually just appeared in front of me from thin air.

I have had him just appear for me, too. But only around a corner.

Also, once I noclipped and found 049 in the LCZ. I don't think he would be able to get there if his pathfinding was so bad.