I think that how uke fits into the realm of how Aikido works is normally not understood for quite a while. Many new students never really get it explained to them, and those that do, have a hard time understanding something they haven't experienced.
Aikido is very different from other "martial arts" and takes years to learn the basics, as opposed to other MA where a studious person can learn the basics relatively quickly (not master them of course). When the theory of how to be a good uke or why we initially attack in unrealistic ways is not explained clearly, then beginners have to try to figure things out for themselves. It takes a while to figure out that uke is there to help nage learn, and while you might initially think that a really strong attack will help someone learn faster, that's not always true. Uke needs to tailor his attack to the level that nage can learn from. For this reason, this guy should practice a bit with the more advanced students to get a feel for what he should be doing. He will learn much faster from them than from you.
You should definitely discuss this with your sensei first.
Also, when this guy is starting to grab you, you don't have to let him get a death grip on you. As you progress, you'll find your reflexes will develop to a point that it's hard for anyone to really get a death grip on you.