East showed
hearts, not spades, 11-15
balanced
3-4-2-4
8 SPs (3/2/1)
♥ - 0/4+ QPs (so AK/AQ)
♣ - y, ♠ - no
5♠ survived.
West's issue was that East could have had ♣Axxx, since that's the same 3 SPs as KQxx. Then 6♠ is basically 3-2 trumps.
This is a regular issue, usually solved by asking for kontrols. That leaves the ♠Q to be revealed. We might do
3♥ over 3♣ as a kontrol ask. Then 5 kontrols = slam, maybe even grand. Otherwise
3♥ - 3NT = 4 kontrols
Now West might take a chance on the ♣Q but still needs to find the ♠Q.
Going round the block again looking for queens in our crude DCB won't work in time. Better methods would solve this.
What we can do is bid 4♦ as a mild slam try, requiring describer to bid bad potential trump suits up the line. (See earlier post)
4♦ - 4♠ = HH hearts, no spade honour.
Pass
Or 6♠ if describer bypasses 4♠

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