Is he seriously ill?

After their emotions calm down a  bit Happy explained Li Yang about the situation in the video while giving him the documents about Rain's situations and other cases mentioned in the video. These were the documents that happy retrieved from the Warerior peaks when he visited there after it's annihilation.

They analysed the similarities and differences in the symptoms that the both of them showed for the next couple of hours while taking care of Elliot in between.

After a detailed analysis and a series of some minor experiments from their calculations, Li Yang finally breath a sigh of relief after analysing the whole situation. 

According to their calculations, if everything was right, they estimated that Elliot will be waking up about the same time which was supposed to be the time when the symptoms for others first started showing, that was roughly fifty hours.