In short MetaTrade5 should be the one fully accountable for creating such a perfect platform for scammers to use.I am very sorry to hear that. In this business, there are more scammers than real traders. Thus, it is best not to get involved or depended with others. I hope you will be able to cover your loss soon. Thanks for sharing your story here. I am sure it will help many of us here.
A person with no trading experience would never thought that the app MT5 which can be legally downloaded from the app store are mostly use by scammers to alter the trades values to cheat their victims.
In additional in the app store review, no one has ever commented that MT5 was used by scsmmer or they have been scammed by using MT5 because the posted comment regarding those scammer will be usually automatically remove by the system.