You should be able to grab it with the PC Controller. I’ve done it with the LightStrip so I’m guessing you can do it with the switches as well.
How you do it is a bit complicated. This is from something I sent someone before, from memory. It’s not the exact set of steps but it’s close enough to help you figure out how to get it:
You have to get it from the PC Controller logging when the device pairs. Add the device to PC Controller as S2 without authentication. (EDIT: This means uncheck the 2 S2 checkboxes.) You then have to look at the log generated when the pairing took place.
I don’t remember the exact line but the full DSK is in there in hex. Disregard the first byte (mine was 0x00). The 5 digit numbers are represented by 2 bytes, so the next two hex values are the first 5 digits of the DSK. Just convert the hex to decimal.
To confirm that you are looking at the proper line, you need to know the rest of the DSK. You can see the entire DSK w/o the first set if you try to add the device to the PC Controller S2 authenticated. Once you have that, convert the 4th and 5th byte of the line you think is correct. It should match the second set of digits in your DSK.