I wouldn't do it.
If you want to act as a halfway house you could try adding a tank divider and (as mentioned previously) slowly acclimate the oscar before dropping him in. At least that would get him in some clean water and maybe with a tiny bit more room.
Why don't you school your friend up on keeping clean water & whatnot instead and in the meantime advertise on CL or ask around the LFS in the area to see if they'd take em.
If you want to act as a halfway house you could try adding a tank divider and (as mentioned previously) slowly acclimate the oscar before dropping him in. At least that would get him in some clean water and maybe with a tiny bit more room.
Why don't you school your friend up on keeping clean water & whatnot instead and in the meantime advertise on CL or ask around the LFS in the area to see if they'd take em.