Phil, I thought the converter supplied the other loads first (same with solar) and anything left over went to battery charging.
But that is between the converter's 13.8v and amps and whatever voltage the other loads bring that 13.8 down to --maybe 13.4.
Here are some PD9200C specs loaded and unloaded
No Load DC Output Voltage 13.6 VDC
Full Load Output Voltage > 12.6 VDC
Now the battery gets any current left out of the converter's size amps that can run between 13.4 and the battery's voltage along whatever R the wire is.
I am not seeing how making the battery AGM vs Wet makes any difference between the converter and running the loads. The converter does that, not the battery.
I am asking, not saying the above is correct, just what I thought up to now. Here to learn!