You're not listening.
The pilot doesn't need to be employed as a pilot. His title is irrelevant. If it can be shown that he benefited economically from the flight in any way, then it's for compensation. In fact, even if he benefits in no way at all, but the flight is operated for compensation or hire or benefits economically (business aircraft, remember?)...he's in violation.
The boss may be taking tax benefits. Economic benefit...airplane's being operated for compensation. Boss pays private pilot for some other title, even has a little business card printed up saying so...makes no difference. He's benefiting, the aircraft is benefiting, and it's in furtherance of a business. Furthermore, he wouldn't be in the role of pilot if he weren't being employed as a required crewmember. He isn't simply a private pilot with a Lear type or SIC type who happened to be going along in the same direction. It's not incidental to his employement, and inventing a title, or even holding a title, other than "Pilot" changes that in no way.
As shown previously, not even public use aircraft...aircraft which can be operated without compliance with most regulation...not even those are exempt from the regulations and policies pertaining to issues regarding compensation or hire.
The FAA has bee quite clear...even the logging of flight time is compensation and violates the privileges and limitations of the private pilot certificate. Even if the private pilot accepts no wage at all...even the improvement on his experience of having he flight time counts as compensation...this from the FAA Chief Legal Counsel. (There are three standards for authority with respect to the regulation and the FAA: the regulation itself, the Federal Register Preambles, and FAA Chief Legal Counsel Legal Interpretations).
If the employer provides training and a type rating, or SIC type in the airplane, then the employer has provided additional benefits to the employee, which may also be termed as compensation and furthering his qualifications.
This can easly be alleviated by obtaining the necessary certification, and doing it right. Go get the commercial. It's not that big a deal. Go get the type rating. For someone with no flight experience and no high performance experience, no jet experience, and who is about to jump from a small airplane to a fast airplane, do it right. Get some training.
I attended a Simuflite course a few years ago for a Lear. In the class were a number of initial applicants with no lear experience; several of them were there for the first time. I had several years of Lear experience and the course was a refresher. I was a little surprised at how much difficulty some of them had, including two FAA inspectors who were getting typed. All described it as drinking from a firehose. Now, admittedly, the Lear isn't a complicated airplane by any stretch of the imagination. The Lear 31 or 35 is fairly docile (whereas the Lear 20 series are not, especially with the older wings). For a new pilot making the transition, it's not like jumping from a 152 to a 172. It really isn't. I've watched new pilots lose control of the airplane on several occasions, including a dutch roll loss that nearly resulted in an aircraft loss.
Sure, the pilot in question in this thread might have a qualified PIC in the left seat...but let's get realistic. What's he going to do when the PIC has a heart attack or is incapacitated in an explosive decompression at altitude? When reality strikes, is that 200 hour private pilot ready to handle a decompressed unusual attitude at night with no references and 5-15 seconds of useful consciousness to get it all right?
Setting aside the legalities, which alone prevent him from taking this assigment, the notion of not needing the adequate training and qualification (and I'm not talking legal qualification) is ludicruous and intensely stupid.