Galax Note 3 and Galaxy S4 in water

I hope that I can properly explain my issue this time and hope to get a response this time. A friend of mine had brought to me his galaxy note 3 that was dropped by his son in water and I have myself the wife's S4 that was also dropped in water. My S4 I put it in the rice and few days later it was back alive but then after few months the phone would start but you cant see anything on the screen. THE SCREEN WAS TOTALLY BLACK. I thought the screen had died but it is flickering when I turn on the phone While my friend's note 3 after he put it in rice we can also hear it turning on but also the screen is black but no screen flickering in the case of note 3. S4 can be read by the phone and can get info and backup. Note 3 undetectable by the PC and cant get info out. does anybody have a diagnosis for both devices. If so what are the remedies that we can use. The S4 might not be that needed since I have extracted all the relevant information and have a new device. But the Note 3 is the main device since my friend also needs the info on the phone and he is welling to forget about the phone if phone is unrepairable


Can I kindly request your assistance with the 2 devices