Does this rule "roll up" if you play multiple provisional balls?

A scenario at the weekend was: -

My partners first drive went into a hedge, provisional played - same result, then a second and third provisional played all into the same wood (the chap was getting a trifle agitated at this point) <grin>.

He play a V. Short ball and we went to search the hedge.....and found at 3 of the 4 missing balls.

He claimed (and I have no reason to doubt him) that he had found his orignal first ball, so dopped out (2) and played the next shot onto the green (3).

I assume he was correct - after all the provisional balls were just that ...provisional - wern't they ? Or did playing a second provisional ball make the original "lost" ?

Nic