But it appears the museum is closed permanently (owner sold off his collection apparently) and the Chateau web site says the Gardens can be visited for groups of 10 or more.
There is a tea room in the Gardens but not sure that lets you into the Gardens to see the views.
Are there other things worth seeing if the Chateau isn't available for visit (I've emailed to ask)? Are there other panoramic points to look out towards the ocean?
I guess if I go to some nearby destinations like Grasse (never been, not sure if there are other draws besides parfum) or Vence, it could be worth the effort to stop by.
I will be going to Verdon and one route may be through Verdon (as opposed to heading west on A8 from Cannes and then N/NW from around Frejus).