Generally, Jsonix is a not-for-profit project. It's about making a good idea work, it's not about selling you anything (licenses, consulting services and so on).
Nevertheless, if you want to use Jsonix in a high-profile project and you need a strong and reliable project partner, my employer, disy Informationssysteme GmbH would be the best choice to secure your Jsonix-based developments.
There might be also freelancing support options via fellow developers.
Feel free to contact me for more information.