I think Virgie Baker states she was "accompanied" by some of the girls including Arnold when she left the second floor to go outside.
Correct, the wording does give that impression
However I think Ms Arnold joined that group outside a little after and Ms Baker simply misremembered four months later.
Cf for example (and from the same CE1381) Ms Judy Johnson, whom Ms Baker includes in the group that supposedly accompanied her from the second floor. She tells a rather different story:
"On November 22, 1963 I left my office, Room 200, Texas School Book Depository Building, about 12 :15 P .M . to go. outside the building to watch the President's Motorcade pass which-was to pass along Elm Street in front of the building . I was with Miss Jeannie Holt, 2521 Pleasant Drive, Dallas, Texas, and Miss Stella Jacob, 508 South Marsalis St ., Dallas, Texas both employees of the Texas School Book Depository . We walked to the southwest corner of Elm and Houston Streets and were joined by Mrs. Bonnie Richey, 220 South Marsalis, Apt . 117, Dallas, Texas, Mrs . Carolyn Arnold, 3325 South Tyler St ., Dallas, Texas"Ms Betty Dragoo seems to make the same error (if such it be, and if the interview statement is indeed an accurate rendition of what she says) as Ms Baker in this regard.