The Plane that Fell to Earth
I suggest you first take a look at the flight plan, before designing the aircraft. This might address my criticism of PARIS which landed very close to the release point, indicating it did not really fly, so much as plummet. I noticed Samsung copied the PARIS flight concept as a commercial stunt, they sent up a balloon with hundreds of paper airplanes with memory chips affixed to them. They reported planes recovered hundreds of miles from the release point. This shows these simple fixed wing paper planes had a good glide slope, flying horizontally for a considerable distance. However, this is also a disadvantage in recovery, unless you have an international team to recover LOHAN across Europe (and perhaps the seas).
So I suggest taking some design cues from model rocketry. There is a type of rocket known as a "boost glider" that somewhat resembles my proposed design goals for LOHAN. A boost glider has two flight phases. First, the rocket boosts to a high altitude, and the boost stage burns out and ejects. Then the glider stage deploys, the wing shifts its aerodynamic qualities from vertical flight to glider. The key factor here is that in order to not chase the glider to a distant landing point, the wings are designed to put the glider into a gentle spiral, circling the release point. This is intended to maximize flight duration without flying the thing in a straight line into another country. This also has the advantage that the characteristics of the spiral flight can be fixed into the design without need for autopilots. In some cases, a simple aileron adjustment is all that is necessary to create the gentle turn required for a circular flight path.
The best boost glider kit I ever built will address some of the problems I see in Murray Pearson's proposal. His folding wing design seems to require a mechanism to unfold and fix the wings into flight position. The design I built was a kit from Estes, with a one-piece solid wing that rotated into place around a central pivot. During flight phase, the oval wing as inline with the rocket body. When the boost stage separated, it released the wing, which pivoted 90 degrees, pulled by a rubber band. This is a much simpler design than Pearson's which requires dual wing deployment. Vintage Estes model rocket plans are archived on hobbyist websites, but I was unable to find the rotating wing design. Still, that was perhaps more of a design stunt than would be necessary for LOHAN. Most boost glider designs have fixed wings that merely adjust ailerons during the flight phase. This would be sufficient for LOHAN, since the balloon will lift the glider during the initial lift phase, eliminating the need for aerodynamic characteristics needed for self-powered vertical flight. However, your proposal for a rocket powered initial flight stage would still require a stable flight platform. I might suggest using an example like the SEMROC Swift-BG design.
It doesn't have any complex unfolding wing design, it's simple and looks effective.