Besides the Rebels and the characters mentioned in the question,
Boba Fett and Bib Fortuna, whose methods of escape haven't been shown in canon yet:
According to the Star Wars Character Encyclopedia, New Edition, the members of the Max Rebo Band—Max Rebo, Sy Snootles, and Droopy McCool—are known to have been on the sail barge and survived, breaking up after Jabba's death:
After Jabba's death, the band breaks up.
Max Rebo's band accompanies Jabba's entourage on the Hutt's Sail Barge.
—page 134, Max Rebo
In The Legends of Luke Skywalker, a mole-flea named Lugubrious Mote claims to have been present as well, surviving by riding on Luke's head:
Her story in the collection is fairly outlandish and is likely intended to be a tall tale, but, notably, includes many details of the battle that would have been hard to learn in-universe without being there.
The only other character known to be present at the destruction of the Khetanna who isn't known to have been killed, or eaten by the Sarlacc, was Saelt-Marae, one of Jabba's goons, popularly known as "Yak Face" out-of-universe.
However, he hasn't appeared in any sources since, so it's entirely possible that he was killed as well.
Several of the same and other characters are known to have survived in Legends, besides the Rebels:
- Saelt-Marae: faked his death, went into hiding
- Hermi Odle: escaped the explosion, stole one of Jabba's ships
- Tessek: escaped on a speeder bike, got turned into a B'omarr monk
- Bib Fortuna: escaped on a skiff, got turned into a B'omarr monk
- The Max Rebo Band: jumped off of the barge, went their separate ways
- Boba Fett: fell into Sarlacc pit, escaped, nursed back to health by Dengar