At which point he'll be doing it well no? And what is a month in the vast scheme of getting stronger anyway.
I'm sure you are correct about the lack of experience, but his lumbar spine looks hypermobile to me, which usually goes hand in hand with hip mobility issues.
That's a good idea.
Are you kidding me with this? Form work is the only thing that will enable him to move big weights in the long run (coupled with heavy training). Sure he'll get stronger if he continues pulling like this, but then he'll hit a wall and won't make gains again until he fixes his form, so why shouldn't he do it now and set himself up for success in the long run. What's more I think he initially asked for help with his form (and probably how to fix it).