That is precisely why this will be settled.
Nobody wants that. It would cause all kinds of problems. For all parties at this point it is best to settle.
It would not surprise me if part of the negotiations included Watson settle the remaining four current civil cases against him and in exchange the NFL agrees to a less severe punishment (4-6 game range) than they originally sought. In exchange for agreeing to such a deal, if I were Watson's legal team, I would require the NFL to agree to bring no further disciplinary action against Watson in the event additional civil cases are brought forward.
It's in the interest of both parties strike an amicable deal and move forward.