A few quick thoughts. Spanier/his lawyers are walking a tight rope. In all likelihood there is not going to be any hard evidence that points to Spanier directing the report from MM to be buried (unless Shultz drops a bomb). But as others point out he is in danger of simply being the only person the jury can punish. So he does not want to do anything that could potentially alienate anyone on the jury. Therefore they decided not to push back on MM, being content to simply point out MM never spoke to Spanier about this, therefore it really makes no difference what MM told Curley and Shultz.
With respect to Raykovitz I think they were content to establish that TC never reported any type of abuse (if MM told TC he witnessed abuse and PSU wanted to cover it up, why go to Raykovitz at all?). I would not worry too much about Raykovitz' retort that TC told him PSU investigated and hence TSM had no need to. Raykovitz knows PSU is not the entity to investigate this type of allegation and TSM should have reported it. IMO this will come back in closing arguments by the defense.
Finally, IMO, if Charles Thompson's recap on Pennlive is accurate, the biggest bombshell, by far, was Courtney's testimony that Shultz told him MM reported horseplay. Spanier is presumably going to testify to the same thing. So if you believe Courtney why would you not believe Spanier as well?
IMO this entire case right now comes down to Shultz' testimony, and maybe to a lesser degree, Curley. If they testify to what they have in the past - MM was vague, sounded like horseplay, Courtney never advised them they had a legal duty to report,,,,, basically the case is over and Spanier may not even testify.
Now, with all that said, the jury can do anything they want regardless of evidence.