The half time drums surprised me recently. I believe it was called 'metal halftime, or such and it did exactly what I was hoping for, played the drums at a half time feel to the tempo. The ACW in Realband would change the actual tempo back, which may/may not be what you want. Not sure if this would be a sneaky work around.. it may keep the song flow as is and rewrite the tempo to what you originally wanted. Unfortunately it would change the MIDI tracks back in tempo too, but if you had them all converted to audio, prior to generating the half time drums (even just for this specific purpose) it may just pull it off. Or just create a fictional piece with the specs needed to create the drum part and bring that file in..
couple of ideas

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