This is my thought process:
Omid Scobie is not naive, he's a bit of a chancer, he has some brains but not vast intelligence, he's vain, he's 'thirsty' (ie desperate), all it seems he has going for him is this gig writing about H&M.
He's been the witting (probably) or unwitting (unlikely, but it doesn't really matter now) source of a serious allegation against a current King and future Queen, perhaps (or perhaps not, it doesn't really matter now) on behalf of Meghan.
People totally unrelated to Scobie or Charles or Kate are coming after Scobie's reputation, livelihood, threats of legal action against him from at least 3 quarters, looks like he's being hung out to dry by the Sussexes, doesn't seem to have any or many on his side. He seems quite alone in all this.
If you were Charles or Kate (or anyone, frankly), would YOU want anything to do with Scobie crumbling under the pressure, doing something awful? This isn't the Deep South, someone fighting for civil rights, standing up to racism and willing to lay down their lives for it. It's Meghan Markle trying to stay relevant when she and her husband flounced out of the royal family. It's gossip and utterly, completely inconsequential.