What is the takeoff decision speed (V1) for a Gulfstream G500?
Your decision speed also called V1 is the speed at which ou have to commit to taking off whatever happens because you won't be able to stop before the end of the runway after that. This speed is related to the airfield runway length, aicraft TOW, temperature and altitude and will change for each take-off. Therefore there is not a fixed value for a given aicraft.
For the G500 I did find this review

Today our take-off weight with three persons on board and 11500 pounds  of jet fuel (one-third of the max fuel) is 60 000 pounds and our computed speeds are V1: 118 kt for a rotation speed (Vr: 123) and a take off safety speed V2: 129 kt.

And this other one

The G500 was relatively light, loaded with 12,000 pounds of fuel for our flight, which was scheduled for 1.5 hours. Takeoff weight was 59,863 pounds, well below the 79,600 mtow. The avionics calculated V1 at 116, Vr 118, V2 132, and Vref in case of immediate return at 136 knots.

As you can see the value changes slightly but V1 seems to stay around 120kts. Your 200kt speed limit and the altitude and range limit related seems more likely to be linked to the 91.117(b) FAA regulation

Unless otherwise authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4 nautical miles of the primary airport of a Class C or Class D airspace area at an indicated airspeed of more than 200 knots (230 mph.). This paragraph (b) does not apply to any operations within a Class B airspace area. Such operations shall comply with paragraph (a) of this section.