Just to temper your expectations a bit this one is very unlikely to be accepted. While the code for that fan game is open source (under GPL2) they make heavy use of Sega's intellectual property and as far as I can tell they do not have an actual license or permission to distribute those. They are operating in a bit of a gray area where the only reason they still exist is because they haven't received a C&D from Sega (because Sega is generally pretty lenient towards fan games).

While the authors of that fan game are willing to take on the risk of redistributing and using unlicensed intellectual property it is very unlikely that the Solus team would be willing to do so as well.

For reference, here is another similar package request where Sonic Robo Blast 2 got rejected: https://dev.getsol.us/T1051