No, the velocity of a satellite and its ability to stay in orbit around the Earth does not disprove the fact that the Earth is spherical. The orbit of a satellite is a result of the balance between the gravitational force pulling the satellite toward the Earth and the satellite's forward velocity.
In the case of a satellite in orbit, its velocity allows it to maintain a stable orbit around the Earth. The satellite is essentially in freefall, continuously falling towards the Earth due to gravity but also moving forward at a sufficient velocity that it continually misses the Earth's surface. This balance between the gravitational force and the satellite's velocity keeps it in orbit.
The spherical shape of the Earth is supported by a vast body of scientific evidence from various fields such as geodesy, astronomy, and satellite observations. There are numerous observations and measurements that confirm the Earth's spherical shape, including satellite imagery, photographs of Earth from space, and the way objects appear and disappear on the horizon.
The velocity of a satellite in orbit is consistent with the Earth's curvature, as it follows a curved path around the planet. While it may seem that a satellite is "staying up" over a flat Earth due to its velocity, this is not the case. The satellite's motion is fundamentally governed by the principles of orbital dynamics, which are well understood and consistent with a spherical Earth.