Squillionaire charges outstanding number attending (4,5)

I believe the answer is:

bill gates

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'squillionaire' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'charges outstanding number attending' is the wordplay.
'charges' becomes 'bills' ('bill' can be a synonym of 'charge').
'outstanding' is an insertion indicator (some letters standing outside or around others).
'number attending' becomes 'gate' (I've seen this before).
'bills' enclosing 'gate' is 'BILL GATES'.

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I've seen this clue in the Sydney Morning Herald.

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