If East bids 3♠ iso DBL then we have agreement that it is GF.
West can open 2♦ and rebid 3♣ to show GF in ♣.
Or West can open 2NT 20-21, but thought his hand was too good for it and not balanced enough. 2♦ followed by 2NT would have been 22-23.
East thought that he didn't have enough for 3♠ GF, and that he had bid enough with the DBL.
So, how should we bid to 7...or 6?