If the fog wasn't coming from the attractions, then where was it coming from? "Alice, scan that fog please." 
Beep,beep. "I detect a 25% toxic substance, Alec." 

Right after the analysis, Alec moved a little faster so he would not touch the fog at all. "This is bad, I bet someone already tweeted about it." As he grabbed his phone, he noticed there was no internet connection. Looking at the frustrated customers, he guessed they had a similar problem.

"Should we try to back entrance?" he asked Adeline, fully aware that it would take them quite some time to get there. All of a sudden an angry woman stormed towards Alec and smashed her purse towards his face. Alec noticed it only right before it would hit him but instead it went right through him, as if he was some sort of hologram. "You can be glad I missed you!" the woman shouted and calmed herself down a bit. "Ma'm, please, we will try to get you out but we can only help you if you stay calm." Alec replied. 

Stepping a little closer to Adeline, he whispered "It missed me? I would've sworn she hit me right in the face but I didn't feel a thing." 

Clearly, the fog wasn't the only strange thing going on.