If you write the drum parts recording live with a MIDI keyboard, I know the issue and unfortunately it hasn’t bee fixed yet
Check this thread out:
brief answer:
“There is currently a limitation in Dorico that if a note has custom playback position data (eg if recorded from MIDI or dragged in Play Mode), then it may not have the playing techniques applied if the position is before the notated position.
Unfortunately that’s the trade-off at the moment, until we’re able to offset the instructions necessary to play the playing techniques correctly by exactly the same amount as the offset you played.”