When its as cold as you stated as it is that cold here in Wi as well it woudl takew a bit for the meat to spoil. I have had deer down for 10 hours or more beforeI found it. The only stench from the deer is usually blood. After you get it cleaned, make sure you clean out thecavity with cold water and hang. As long as the meat is kept cold and clean you should be ok up to 24 hours. After that i wouldnt use the meat. But please make every attempt to find the deer. Make grid pattern seaches with 2-3 more people. Good luck.