Hello,
You leave behind the A87 at the Tomdoun turn-off to reach Loch Quoich....I don't think that the road thereafter carries any B label?
It has been a very snowy winter up there but the snow at the road level should be clear now.....my daughter has been working near to the dam all winter and recently we have not received any images of snow on the road.
Is it maybe Buidhe Bheinn?, access from the end of the road at Kinlochhourn, that you are thinking of as your alternative?
A road for careful driving.