Sadly there is no hard and fast rule about this - it can be read 2 ways.
1st - he is not part of the formation and combined with the fact special rules do not transfer unless specifically stated, he would stop the whole unit using he rule.
2nd - he becomes part of the unit for all rules purposes and as rising crescendo is not a special rule from the BRB but a formation rule, he would be conferred the rule.
Both are valid readings - ask your opponent!
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