I have now received unanimous psak from a number of noteworthy rabbonim on the negiya between the beis and the shin posted some weeks ago on this forum. As I feared, the negiya is unable to be scraped and the parsha needs gnizah.
While the outcome of many of these tricky shailos are toloi leinei hamoreh, It reinforces to me how important proper training for a magiha really is. As mentioned in the first post, I first encountered this particular shailo when doing shimush years ago. The shailo only came up once (out of thousands I saw and recorded) and I have rarely encountered it since. Please don't take this the wrong way, my intention is not to show off or put anyone down who made light of the shailo. Rather, my intention is just to marvel at the fact that had this shailo not come up that one time during my shimush 15 years ago, I probably would have just scraped the negiya of last week and not thought twice about it. For me, that's a scary thought and reinforces, in my mind, how important comprehensive shimush really is.