Prayers, of course - But it sounds like he is pretty geared up and knows the score - If he is dug in, there is a good chance he is alright. A few days in a snow cave may not be comfortable, but it is alot better than the alternative. There is good reason to hope.
Many thanks for your kind and encouraging message - and you have been proved right. Tim Holding has been found alive, and reasonably well.
It is great to see a news story have a good ending.