Missable.
This took me a bit of work but mostly requires a good setup on your screen. First, shut off the music ... it'll distract from hearing clues. And this is mostly about picking up audible cues.
Next, fiddle with your monitor/TV settings to boost the picture color. Contrast changes can help but may be distracting. You're looking for the ability to detect subtle changes in the cobblestone pattern to determine your direction.
Here are the directions and a few tips:
1. Head east until you hear the sound of dead beetles; it'll sound like soft crunching. As you leave the start/entrance, you'll first hear rushing wind and then a muffled sound (like carpet or soft snow). Both of these sections are short ... the wind is easy to detect but the snow and beetle sounds are subtle and you really need to be listening for them.
2. Head north until you hear echoes. Here, if you've tuned your screen properly, you should detect the cobblestone pattern changing so you can tell you're going north (up on the screen). The echoes should be easy to hear.
3. Head west until you hear the sound of water from a broken pipe. Once you hear the sound, stop. I didn't have to worry about "centering" myself on the hallway. Just stop and turn.
In this case, you should hear dripping water easily.
4. Head directly north until you find the odorless gas. I didn't hear anything here but was pressing my stick to the right (east) so that I could find the first hallway to the east. By looking at the cobblestone patterns I could see when I started to move NE and was then able to correct and just head east.
5. You should now be going east and should continue until you hear a sound of creaking boards. This is easy to hear.
6. Head north and use the same trick of leaning the stick to the right (east) so you can find the first intersection. Once you determine you've been allowed to move NE, change to point directly to the east and keep heading that direction until you hit Igor's room ... it won't be long.
After you find the room, the cupboard is on the left side of the bed ("north" of the entry) and will contain Igor's suit.
Fortunately, you can just click the "back" button to go back to the lobby; you do not need to retrace your steps.