All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
This transaction includes two grave violations of Sharee‘ah (Islamic law) rules: resorting to trickery to commit Riba (usury) and cheating. You should know that the trick that you resorted to does not make Riba lawful; on the contrary, it increases its gravity as this is similar to what the Jews did when they made lawful what Allaah The Almighty prohibited through trickery.
The reality of what you are doing is a Riba-based loan whereby you will take 200 thousand and repay it after a while for 260 thousand. Your brother's participation is void and has no effect.
Hence, you should repent to Allaah The Almighty and give up this loan as no one knows when he will die, so you should not continue with this loan.
Allaah Knows best.