So the assumption is that on shore power your batteries were not being fully charged and the solar spent 2 days bringing them back to fully charged.
Solar controllers can only report the power that is output. If there's no load, output is zero and zero is reported. The batteries and loads control the output. The controller maximeses panel yield and offers what's available to and loads/batteries. It's not possible to work out the difference between available power and output power.
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