1. It looks like https://play2x.com is the main developer of this script or at least the main casino that uses this script as they have a gaming license and most games are tested iTech Labs.
2. This script is also available here from https://demo.playin.team where you get the latest update and 17 games. The price seems to be $1000, so is not much more when you get an updated version and 2 extra games.
3. Everybody has the right to ask as much or less they want. The customers decides for themselves