I have no medical background, but the physiotherapy helped because you were stressing the meniscus am I right? It seems contradictory for the doctor to tell you not to provide stress to the tear but still send you in for therapy... It would seem that you should provide stress to the injury to promote recovery. Just don't overdo it. And no, I wouldn't leg press if you can squat correctly and safely.
Keep the squat weight low and with high reps? Others can probably expound on this.