All vehicles on the AGR complex have been accounted for at the time of the shooting, except for an Alpha Romeo that likely belonged to Greg Nicol. So, he either never parked it there, not including his morning visit to the rally site if he parked at AGR then, or he did park on site then drove it off site before the shooting.
The only Elantra we saw was parked in the street across from the AGR main entrance. That would align with Jon Malis’ dashcam video which captured him walking next the sign like he just crossed the street. Unfortunately the clip presented by News Nation cut off before it got close enough to tell if that car was parked there. I can’t find a reliable source that says what color it was, but I did read unconfirmed accounts of it being red and another that said grey.
What amazes me is there was nothing in the news about the car being checked by the bomb squad or being towed away. All we are told is that he parked near the rally.