I don’t know much about electrical systems and you have already been given advice that is better than I could give. I would suggest that you check to see if your charger has a “custom” setting beyond simply flooded and AGM. If it does, then set the 3 stage charge profile to that recommended by your battery manufacturer.
I have two different types of AGM battery banks on my boats by two different manufacturers. While both are AGM, they have significantly different recommended charge profiles. My point is just that if your charger only gives you two choices, flooded or AGM, then just pick AGM and don’t worry about it. However, if it gives you a custom option, then match it to your batteries.