Unfortunately, in my anecdotal experience schools not infrequently do not fulfill the role of advocate well. (Sometimes, they do, though.)
In a case like this, I think it can somewhat be "luck of the draw". With the initial/primary contact point with the school being the professor, some professors know what to do or at least will tackle the problem. Others are at a loss, or don't care. (I'm not saying that's the case, here; they did pass him, although leaving him without a thesis project.) Remember, you're dealing with an academic, when what you may need is a lawyer.
Unfortunately, in my anecdotal experience schools not infrequently do not fulfill the role of advocate well. (Sometimes, they do, though.)
In a case like this, I think it can somewhat be "luck of the draw". With the initial/primary contact point with the school being the professor, some professors know what to do or at least will tackle the problem. Others are at a loss, or don't care. (I'm not saying that's the case, here; they did pass him, although leaving him without a thesis project.) Remember, you're dealing with an academic, when what you may need is a lawyer.