Is transferring money to Faysal Bank in this manner permissible or forbidden? And is the assistance provided to the brothers considered a deliverance from usury? And is it obligatory to adhere to the 40% profit margin mentioned by Sheikh Ali Al-Salus?

You are right to transfer your account to a non-usurious bank. Placing your money in an investment account with an Islamic bank is permissible, and the profits are halal; the general principle is its permissibility. However, if you know that the profits include a percentage from forbidden transactions, such as purchasing treasury bills, then you must dispose of that percentage. The reliable scholars in your country are the ones who can advise you on this matter. The statement that Islamic banks are like usurious banks is incorrect.