Samsung Galaxy A5

I have this phone from a client, it was owned by her daughter who sadly died. But she also took all the pincodes etc with her.
Its locked with knox, its no simcard in the phone, but it asks for pincode when i srat up. I have tried several programs to unlock this, but it seems that its impossible. But if i either do a jtag, or chipoff, and use ufi-box or something like that, will i be able to recover data from it?
I can get it both in rescue and download-mode.
Oh, and btw, i have done something, now it just stops at Samsung Galaxy A5-screen, its stucked there....