Reddit: I think a coworker of mine may have done something awful. What can I do to help?

UPDATED BELOW

First off- I'm sorry for errors as this is written in my phone. I work with this incredibly creepy older man. He's just the type of guy who makes you feel uneasy. Most of my younger coworkers have said this about him. He is single and divorced.

He currently moved in with another female coworker of mine. This girl is single, not married, has no children or family in the area. She used to live with a friend before she moved in with the creep. The female coworker has told us of financial issues she has, she has no car, and wanted to move close to our work-this is where the creep offered to move into an apartment with her, as he wanted to be closer and has money issues as well. From what I've heard, it seemed platonic. They shared expenses and since he has a car, provided transportation.

Since she doesn't have much money, she has shown herself to be the type of girl to come in very early, stay late, always works overtime and never turned down extra weekend time. Yesterday however, she just never showed up to work. No phone call, no explanation, nothing. Its so very unlike her; Enough to cause concern in the office. My bosses made repeated attempts to contact her, as did her temp agency, but nobody has seen her. Her phone is off.

A few coworkers asked the creep where she was, since they know he lives with her. He acted pretty irritated and appeared visibly panicked-Stating that she was just sick and she had contacted our bosses and called off. (I'm very close with one boss, who confirmed this was a lie and that nobody has heard from her.) He kept diverting away from the topic.

Another coworker noted that on Monday evening, when both the creep and the female coworker were about to leave, he disappeared for close to 20 minutes leaving her angry and confused as to where he was. (as the owner of the only car, the creep is her only ride back to the apartment they share) They both left shortly after he came back. They both clocked out.

About an hour or so, the creep comes back the office-dressed in completely different clothes and appeared to be freshly showered. He clocked back into his computer and started working all over again. My coworkers all thought his behavior at this time was one of someone who appeared paranoid of something. He kept taking phone calls on his cell until he left the office late at around 11:30pm.I (confirmed by the one boss who was working from home and saw him online around that time)

She never showed up Tuesday.

The creepy thing is, she had confided in another coworker that on one evening when she was almost asleep, she woke up and found the guy in her room just starting at her as she slept and that she want sure this was a good idea to move in with him.

I realize this is a huge jump to conclusions, but this is incredibly creepy. I am terrified something happened to this girl. Should the coworkers share this info with our bosses if she doesn't show up tomorrow? Our should we/I just butt out. Theres no concrete proof anything happened, but his odd behavior these past few days has been worrisome.

TL;DR: I think my creepy coworker may have hurt or murdered a girl I work with.

UPDATE- She is okay. She just randomly showed up this morning. She was here when I got here at 9 am EST. My boss finally got a call from her this morning and she stated she'd be in. She hasn't talked to anyone about what happened or if anything bad even happened-just stated that she had the flu, and that she was sick. The "roommate" on the other hand, isn't here. He just never showed up- No idea how she got here either, as she doesn't have a car. Hopefully she moved out.
No idea at all what really happened with this girl or the creepy roommate. I for one am glad I saw her this morning and even more glad he isn't here. I honestly think a lot of this was fueled by concern for this girl, the fact that he is incredibly creepy, and pure office gossip. I appreciate a lot of the response, because it helped me really get the courage to do something for her, even though I was pretty terrified. Just super glad she's okay.

Edit 2-In case anyone wanted to know why I didn't confront him or follow him home, I am a young woman in my early 20's. I'm 4'11, pretty tiny and not very strong.