"Sonny Fiston" is a parody/tribute reference to boxer Sonny Liston.
Page 5, panel 4: Sarge's name is misspelled on his boxing jersey as "Orville Snorkle". Nothing in the story points to it being a gag, so it could just as easily be an editorial mistake.
One of a long-running series of Beetle Bailey comic strip and comic book gags where Sarge finds himself hanging on to a small branch, after having fallen off a high cliff.
All characters appear in dream-form, with only Sarge appearing as his "real self" in the final panel.