I think any guess with this limited info would be mostly speculation. I can tell you my lake is 22' deep at 10,000' in the mountains. I am guessing you and I probably see fairly similar Winter conditions. Our lake Winter killed every year for the last two decades as far as I know. I installed aeration in Summer 2017 and this past Winter was the first year I ever had fish survive the Winter. If you could get some current DO and Temp data it would go a long ways towards a more definitive answer to your question.
