Meekly surrendered primitive shelter before row (5,2)

I believe the answer is:

caved in

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'meekly surrendered' is the definition.
Although both the answer and definition are past participle verbs, I can't understand how they can define each other.

'primitive shelter before row' is the wordplay.
'primitive shelter' becomes 'cave' (I can't justify this - if you can you should give a lot more credence to this answer).
'before' is a charade indicator (letters next to each other).
'row' becomes 'din' (both can mean a loud disturbance).
'cave'+'din'='CAVED IN'

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I've seen this clue in The Times.

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