Distraught re nurse, I can guarantee (7)

I believe the answer is:

ensurer

'i can guarantee' is the definition.
(someone who ensures or guarantees something)

'distraught re nurse' is the wordplay.
'distraught' is an anagram indicator (an unsettled or upset order of the letters).
're'+'nurse'='renurse'
'renurse' anagrammed gives 'ENSURER'.

(Another definition for ensurer that I've seen is " One makes certain".)

I've seen this clue in The Times.

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