Deny true version about keys (6)

I believe the answer is:

refute

I'm a little stuck... Click here to teach me more about this clue!

'deny' is the definition.
(I've seen this before)

'true version about keys' is the wordplay.
'version' is an anagram indicator.
'about' is an insertion indicator.
'keys' becomes 'ef' (I can't explain this - if you can you should give a lot more credence to this answer).
'true' anagrammed gives 'rute'.
'rute' going around 'ef' is 'REFUTE'.

Can you help me to learn more?

(Other definitions for refute that I've seen before include "Prove wrong; deny" , "Disprove" , "Prove something to be wrong" , "Prove to be incorrect" , "Negate" .)

I've seen this clue in The Mirror.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.