Everyone was close.
Vne is predicated on Vd (Design Dive Speed, not venerial disease), which is based on Vc (Design Cruise Speed, not viet cong), and is equivilent airspeed (EAS), in accordance with 14 CFR 23.335, and 23.1505. This is for certification purposes. Speeds are calculated in knots.
Ultimately, the manufacturer may choose to represent these speeds to the customer in any form; calibrated or indicated, or even equivilent. The manufacturer may choose miles per hour for marketing purposes, or knots for traditionality. Or any combination of these.
What the manufacturer won't do is present these as true airspeeds.
For any given indicated airspeed, true airspeed may be greater or lesser than the rule of thumb values discussed hereto. TAS is a function of density altitude, which means that it varies with pressure altitude and temperature. Adding 2% per thousand feet doesn't account for changes other than standard pressure, and doesn't account at all for temperature.
With an increasein altitude, TAS increases, but indicated airspeed decreases. That is, for a given indicated airspeed, TAS increases with density altitude. One may remain at the same pressure altitude and fly to a warmer temperature, and see an increase in TAS, or one may remain at the same temperature gradient and climb in pressure altitude and see an increase in TAS. An increase in density altitude, comprising temperature, pressure altitude, or both increasing together, means higher TAS.
For a given TAS, indicated airspeed decreases with altitude.
Unanswered, you're wanting to know why the TAS can exceed Vne without a problem, while that isn't the case for IAS. Think about how we obtain indicated airspeed. We must go faster and faster with an increase in altitude to produce the same pressure against the airframe, and in the pitot tube to produce the same airspeed. Our TAS is increasing as we go up, but we're flying the same indicated airspeed. A different way to think about that is to say that if you stick your arm out the window at sea level, you'll feel a certain pressure against it, a certain resistance. You'll be screaming along a whole lot faster at altitude, even though you're only indicating the same airspeed, but you'll also only feel the same push against your arm that you did down lower.
The air is thinner, so it doesn't load the airplane as much. Indicated airspeed is a much better indicator (up to a point) of what the airload is doing to the airplane. Therefore, TAS doesn't mean much to the aerodynamic load on the airplane, where IAS gives a better idea of what's going out outside the airplane.
Now, as for the question:
An aircraft is flying 2 knots above stall speed with a 10 knot headwind. He makes a 180 turn and now has a 10 knot tail wind. What will happen?
At two knots above the stall, the aircraft will either descend in the turn, require more power, or stall while trying to maintain altitude in the turn. In a perfect environment in a nonturbulent, nongusting airmass, the aircraft will experience a change in ground speed, and assuming a level turn and adequate power and appropriate use thereof, will complete the turn at the same airspeed as that at which it entered the turn.
In the real world, two knots above stall and horsing the airplane into a turn is a good way to stall, especially in gusty conditions. To say nothing about the hotly contested, theoretically impossible, downwind turn and attendant (in this case) stall.
On the topic of zero groundspeed flight, I've effectively hovered (not a true hover, but a really, really slow vertical descent) into a tiedown spot and done vertical landings in light airplanes, with enough wind. Certainly it can be done, and is done. Consistent wind conditions are the safest circumstance under which to do it.
