No way in hell is this going anywhere above a private settlement. CBS has way too many way too good lawyers for exactly those type of situations.
The only real question is if the settlement is good enough for him to pay for his own lawyer's cost, or if he is going to sit on them.
Depends on what the guy's lawyers agreed to. They may be of the "If you win, we get XX% of the settlement. If you loose, no legal costs beyond court costs (which could be substantial IF they go into a Discovery phase <--- Yes, that's a legal term, not a pun.)
Again what will probably happen is CBS will file a Motion To Dismiss; and based on how the Judge rules on that, they'll start talking settlement as with stuff like this, it would have to be 100% meritless (IE even a Judge thinks no Jury would buy the Plaintiff's arguments, or said arguments in the Pleading have no basis in law); and that's not the situation here - he's shown enough that I believe a Judge would put it in front of a Jury.
But yeah, unless his legal team somehow believes he could win big; once/is the trial gets past the Pleading stage, I'm sure both sides will agree to some sort of monetary settlement and move on. The Discovery phase can cost a lot to both sides, and might hamper series production if Producers/Writers/Cast have to take time to do depositions; so if the guy's smart he'll take a settlement.
The instantanious travel was possible without a tardigrade. They were never needed to make that happen. They were just needed to navigate the mycellion network and Bryan Fuller has documented interests in Stamets, Mushrooms, and Mycellium network prior to DSC.
So DSC could travel instantaneous WITHOUT a tardigrade and did. In his game, travel required a tardigrade to hug you to transport you
Where is the theft?
Well, not quite. Yes, the Tardigrade's brain was required, but the Tartigrades DNA was also compatible with the spores and both elements were needed (IE Spores and a functional Brain to direct them).
The issue the Federation had was that to make a Human compatible with the Spores to the same degree, Genetic manipulation was required <---- Which since the Eugenics was illegal; hence what Stamets did to himself was illegal; but since it was successful, and there was a war on, Starfleet preferred no charges, but said, "Hey you're it, don't try this genetic manipulation on another Human again..."
But yes, IF the game states the 'Universe Travelling' is all part of the Tardigrade itself (no outside fuel or other elements needed); that is in fact a large difference between ST: D and the game.