Transport directions help

Hi,

A friend and I are heading to Mt Fuji for one night from Tokyo during december on a weekend. There seems to be transport to kawaguchiko station but how do I get to lake yamanakako (hotel mi-fuji)?

"Take the JR Chuo Line from Tokyo's Shinjuku Station to Otsuki Station (70 minutes, 2700 yen by direct limited express train or 100 minutes, 1280 yen by local trains with usually one transfer along the way). From Otsuki, take the Fujikyu Railway Line to Kawaguchiko Station (55 minutes, 1100 yen one way)." -from japan guide

Do you have any suggestions and how long will the journey take because I have a flight to sapporo the next day at 2:40pm? I am worried that I won't be able to make in time since Narita Airport is quite far away.