He's weak, detrained, and has poor soft tissue quality, among other things. Luckily, in a squat or a deadlift you don't need to internally rotate the femur at the hip. Can he squat relatively pain free? O/A is a bugger, honestly. Medications, getting stronger, and fixing lifestyle issues like diet/sleep/stress tend to help but not eliminate O/A, as it's more of a wear and tear pathology resulting in some people having structural changes to the joint itself. If he can't squat- then perhaps he can deadlift.
Weakness, in general, can be mistaken as "tightness"- as weakness tends to correlate with less volitional control of the skeletal muscles- including relaxing through a passive ROM or moving through an active ROM.