Mine too are all single words but I am puzzled by 15a. I have two of the three letters and I'm reasonably sure of the solution but I can't parse it. A hint (Ha!) would be much appreciated.
15 A. Remain undecided, lacking hint from photo finish (3).
Your answer will fit the last word- it comes from a 4-letter word meaning 'remain undecided '. Lacking hint from photo is just a usual crossword instruction,for dropping a letter.