The theory that a fee (which I still don't understand what the fee is for nor who pays it and for what) is consideration for the PROMISE that the divy would not be recalled, IMO, is nott a winner.
TDA's receipt of the fee was nott conditioned upon the client believing the PROMISE that the divy wouldn't be recalled. The fee may have been consideration for the PAYMENT of the fee, butt nott for the PROMISE that it wouldn't be recalled.
Tell me more about the fee please anyway, because I am curious about it.
The only client theory I can see is EQUITABLE estoppel under a theory of detrimental reliance if TDA comes after the client, which as I've written previously is really nott a winning claim in these circumstances.
For the promissory estoppel claim, remember that the CONSIDERATION that TDA must have been given by the client must be consideration for the PROMISE that the divy will nott be recalled, nott for the payment of the dividend itself. The client did nott make a choice to receive or nott receive the divy based on a representation by TDA that it would nott be recalled. It was paid BEFORE any such promise was made.
HTH.