Depending on the circumstances it actually CAN be against the law to pressure someone like that if you're paying them for a massage and pressure them into something they can easily claim later they were coerced.
I just think the sheer number of women is working against him, even if the courts do decide as you said the NFL is still looking at a guy who had 22 complaints, apparently some confirmed as to he coerced them, I can't see them just saying ok he already missed a season that's good enough?
If there's really a grand jury jail is clearly possible, the reason they convene grand juries is they want to accelerate the case, and Grand juries are completely secret. If the GJ finds Watson innocent none of what was said in the testimony gets out, the accusers don't get paraded through the media, witnesses are not made public. and the prosecution has more control so they can get to a conclusion faster which in most cases benefits both parties.
But I can't find anything more current than early Dec and that was just Watson's lawyer saying we're very confident and not saying why beyond my client is a good guy