He is not going to play, and he doesn't have to be 'optioned'. He is already in the minors. I'm not going to do the research, but if we go back and look at the first 10 spring training games over the last five years, the number of ABs, total, that went to players who weren't actually in major league spring training has to be in the single digits (each year). Typically they bring over a few pitchers to pick up innings, or a good prospect who isn't yet ready for the full invite, just as a ceremonial thing. They already have as many as 6 CFs (Haseley, Quinn, Kingery, Martini, two non-roster guys) and Nick Williams (and some of the infielders) as lefthanded bench bats on top of that.
Beyond that, the reality is that even if we had two OF injuries, just on merit, the Herrera we've seen for his last 500 ABs is not actually any better than the AAAA guys (also you could play Kingery in CF and try other guys at 3B), just like Maikel Franco wasn't really better than Sean Rodriguez. We're just wishing on what once was, and our fondness for him, never mind the arrest. Even Nick Martini (the guy we DFA'ed him for) had a higher OPS last year. And even if he was given the chance to get 50 ABs in spring training and was good, it wouldn't really mean anything (bad players, or players who aren't actually ready, tear up Clearwater all the time).
But we shouldn't forget the arrest either. Again, zero tolerance isn't necessarily the answer. But I (and probably at least half of the phan base) have no problem if they've simply decided they don't want an accused domestic abuser on the team. They're just not allowed to say it, which is actually kind of silly.
If they really want him or even want what is best for him there is simply no reason why he wouldn't be invited to spring training, and really no reason why he couldn't be on the 40 either (I mean, c'mon, there's always a way to free up a spot. Heck, why even keep Nick Williams compared to a guy who can play CF?).
I still think being released or buried in extended spring training is far more likely than him walking onto the field in Allentown.