You can also create a fade that targets an entire cue list. If your entire show is in a single cue list, you can set the target of your 2-second fade cue to that cue list, assign your Bluetooth keyboard hotkey as a trigger for that fade, and you're set.
If your show is on multiple cue lists, you could have a group cue with individual fades, each targeting a single list, and set your hotkey trigger for that group cue.
Sounds like you've found a solution, but I'm chiming in anyways like the loud-ass I am.
Dan