The sound in the bus is a product of all sends interacting with each other. The mix functionality of the plugins and the bus combined are the sound you consequently get to hear. This sound will always be entirely different when you process the sends individually and play them back together afterwards.
What are you trying to do anyway, if I may ask?
Have a nice day!
In theory this might work:
Create a send on all relevant channels to an unused bus, set the levels to 0.0 (the actual amount will be determined by the fader & any volume automation). Set the output of the channels you don't want to bounce to "no output," as well as on the corresponding AUX channel that was created for the new bus (you could also just delete the AUX). On the compressor that is on the summed channel, set its side-chain to listen to the new bus. Now this compressor is listening and reacting to all drums, yet the only sound passing through is the one channel you have not changed to "no output."
I'd be curious if this would pass a null test, but won't be able to test myself for several days.
Sereen, this looks very convincing and very logical and in theory it should work. But I would not bet on it. Never ever will it sound the same. The resulting energy of the tracks mixed together is different. So you are right in respect to coming near the original, but when you A-B the difference will be obvious.
Nicely thought though!