I like what you're saying, but want to inject a less violent way the person got her into his car. I think they spoke in the parking lot at work and then he followed her home. I think cameras picked them up at the MetLife parking lot, then caught (on camera) both of their vehicles leaving around the same time. I think that's why his home and car were searched,
Since it's likely they knew each other from work, and he was in a position of authority, and she was very sweet and trusting, I think he took advantage of all that and lured her into his car with some knowledge he had about her.
Based on what we know about Dannielle on a superficial sleuthing level, I think the two simplest possibilities include:
1) He surprised her, saying he forgot to tell her 'one other thing' about something. Possibly his sick wife. Maybe he mentioned blood donations or something he knew she wouldn't blow off. Or
2) she willingly invited him to follow her home to make a quick buy in her own parking lot, away from work.
Whatever the lure, I think she voluntarily stepped into the car but everything went sideways immediately following. I wouldn't be surprised if a gun was involved at that point.