I fail to see in what way your analogy could even be remotely applicable uknighted.
Shore Capital and Winterflood sold shares to retail customers. In order to make sure that they could actually deliver shares they bought some from Evo. Evo failed to deliver them to SC and Winterflood thus causing SC and Winterflood to have consequential problems.
If you think that this therefore means that Shore Capital and Winterflood are guilty of some heinous crime then frankly you're in cloud cuckoo land. But I suspect that your legal team will have already told you that. It's just a pity that you had to waste so much money to be told that.
We are revisiting old ground though and on the face of it you do not yet appear ready to admit that "Shore Capital and Winterflood were only dragged into this affair as a consequence of Evolutions' mistake". Ce la vie.