Maybe also think of it like this:
Scenario A: Jacobs starts the season on commissioner's list, paid leave. The League files a request for the security footage but they don't receive the footage until sometime in Week 12. The league reviews the footage and finds that it doesn't show anything too egregious and they give Jacobs a three-game suspension. He gets to keep the wages he collected from Weeks 1-12 and just has to pay back three weeks' worth of checks. He is able to return to play immediately in Week 13, having already completed his suspension.
Scenario B: Jacobs starts the season on the commissioner's list, paid leave. The league files a request for the security footage but local PD doesn't provide it for them and Jacobs himself refuses to provide video. The league decides to make a decision without the video footage, and based on just the court proceedings, pleas, charges, etc, they give Jacobs a 4-game suspension. Having already missed four games he is able to return to play immediately. A few weeks later there's some chatter about the video footage leaking out. TMZ gets ahold of it and it spreads like wildfire. It's really graphic and violent and it turns out that Jacobs and his camp had paid off the victim to try and lower the charges and keep quiet about the issue. The league can't suspend him twice for the same offense (this is precedent) so they're stuck with their hands tied. There's massive blowback against the league in the media.
Now I think "Scenario A" or something like it is FAR more likely. And I would readily acknowledge that "Scenario B" seems awfully unlikely and is wholly speculative. There's no reason for me to believe that's close to the truth. BUT that's besides the point - the point is that "A" is a perfectly acceptable outcome from the league's perspective. They have no issues whatsoever if it plays out like "A". On the other hand, however unlikely it is, "B" is an absolute nightmare worst-case-scenario outcome for the league. That's the scenario that they want to avoid at all costs, and the current CBA gives Goodell full power to do everything he can to avoid that kind of scenario. If they think that there is even the tiniest possibility that something like "B" would come to pass, they're going to err on the safe side.
I think that's pretty much the basics of it. I'm not saying I agree with every aspect of the approach, nor am I really trying to issue any judgment (good or bad, one way or the other) on Jacobs or the case itself at that point, but just talking about the practicalities of it all. The bottom line is that from the league's perspective it's about risk management and they have zero incentive to take on any more risks than is absolutely necessary with this case.