shibazakura festival to kawaguchiko

For the sake of convenience, I had booked a bus from shinjuku bus terminal direct to the shibazakura festival site. I was wondering would I be able to ride the liner or get any public transportation (other than taxis) from there back to kawaguchiko? I could not find any information for such one-way bus travel. Would appreciate if anyone has any info if such travel is possible and how much would it cost.

Take shuttle bus(not need booking).
http://www.shibazakura.jp/eng/access/index.html
[time table]
http://www.shibazakura.jp/liner/index.html
富士芝桜まつり会場(park) → 河口湖駅(kawaguchiko stn)
around 1200Y/30min maybe.
1800円(Y) means round discount with park fee.
No regular oneway fare info.

Thank you so much for the information. 1200yen does pretty steep for a oneway bus ride which makes the 1800yen park package seem like a good deal. Yes, I can't seem to find any info if one-way travel back to kawaguchiko online. Thanks again for your help.