The most common and most likely answer to this crossword clue is the 9 letter word EXPLAINED
I've seen this crossword clue in Financial Times
E
X
P
L
A
I
N
E
D
More clues leading to the result EXPLAINED
Buddy explains!

The straight part
We know that "Accounted for" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case accounted for = explained.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does EXPLAINED mean?
EXPLAINED verb- To make plain, manifest, or intelligible; to clear of obscurity; to illustrate the meaning of.
- To give a valid excuse for past behavior.
- To make flat, smooth out.
- To unfold or make visible.
- To make something plain or intelligible.