AverageIFS Error when using multiple columns for Average_Range

I have a WS that has 3 columns of data I want to average, based on the date/time being within 90 days of today.

Column A has Date/Time
Column B, C, D have results for each date entered
Cell C1 has

Formula:

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If I use the following formula and receive a numeric answer

Formula:

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If I expand the Average_Range (first section of function) to include multiple columns, I receive an error of #Value!

Formula:

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Can someone smarter than myself help me? Thanks!