He was accepted into the university but still has the choice to abandon it.
Why would he even consider "abandoning" it, especially since losing the opportunity to attend that university would the exact worst-case scenario he'd fear, if he
were being blackmailed?
His ghostwriters are not blackmailing him, but they have not received the money yet.
First, if he agreed to pay them after they did the work for him, and they fulfilled their end of the agreement, why hasn't he already paid them, as agreed? Second, why would he assume that they're going to blackmail him after they (apparently) did a good enough job on the project to secure the successful outcome that he sought? In all likelihood, the writers haven't even thought of doing that and are just waiting to be paid whatever they rightfully earned for their work.
Blackmailers are
always phony "writers" and phony companies that
can't actually provide quality work; that's why their whole "business model" is blackmail
instead of writing, in the first place. Legitimate writers and companies don't deliver high-quality work and then blackmail their satisfied clients. Blackmailers either provide nothing after being paid in advance or they deliver completely unusable garbage and the blackmail is their response to customers' rightful demands for refunds, to try to make them go away and just eat their losses. In your friend's case, he seems to have received exactly what he hoped to receive, and then used the work successfully, and he hasn't received any blackmail threat, right? So, why would he be considering abandoning his plans to attend the university instead of simply paying his writers?
In almost 20 years on this forum, I've only heard of one or two accusations against any legitimate writer ever threatening or "doxing" a customer, and it was because the customer fraudulently cancelled the payment after the writer delivered exactly what he'd promised to deliver. Legitimate writers hope to convert every satisfied customer into a long-term repeat customer. In fact, a successful admission essay is perfect in that respect, because that's a student who will probably use the same writer all through his university studies; and four years of regular paid work from a happy customer is worth much more to any (real) writer than some lump-sum payment generated through blackmail. Blackmailers don't really write anything and legitimate writers don't blackmail anybody. So, why would your friend want to give writers who, apparently, did good work for him a legitimate reason to be angry and possibly motivate them to retaliate against him for ripping
them off by not paying whatever he rightfully owes them, especially when your friend
hasn't already been blackmailed?