Yes, everyone stays tentacle free. You have to make certain choices and have gale ok with becoming a bomb but other than that yes everyone lives except the emperor and gale.
Edit: For anyone who wants to see this here is how I remember doing this ending:
Act 3 & Ending spoilers
spoiler
Step 1 make sure you have the hammer to free orpheus
step 2 tell Emperor to fuck off
step 3 open orpheus' orb
step 4 tell orpheus there is a way without him sacrificing himself and no on needs to transform
(there might be an option to talk to Gale here to make sure he's cool with going boom but I don't recall 100%)
step 5 get to the brain stem with Gale and company
step 6 have a final convo with Gale and send him up
Gale nuke (Act 2) means Orpheus probably gets munched by the Emperor. Act 3 is basically the same as everything else but Gale kamekazi's at the last minute meaning Orpheus got munched, Tav/Karlach transformed, or Orpheus sprouted.