Kudos to you for taking figuring out the path through the lake for the rest of your fellow pellegrinos. This is the kind of thing my "real-live cowboy" uncle taught us when we were small fry and following him through the brush and creeks of eastern Oregon... pick a path and go forward until you have to pick another path. (He also said to watch out (or listen) for rattlesnakes, too, but that probably doesn't apply on the Camino. ;>)
As someone mentioned above, it's only water, and if it comes in over my gore-tex hiking shoes, well, I just stop and empty them out once in a while. And I'm careful to stuff them with old newspapers each evening (bars are a good source of old newspapers) to be sure they are dry by morning.
Along the Via Francigena in both the Alps (Great Saint Bernard Pass) and the Apennine Mountains of Italy, there are warning signs about not crossing streams running above the stepping stones (like someone must have done before and got into trouble, no?!!). Atmospheric rivers are becoming a factor in several places we all like to trek... be prepared to deviate from the paths and do some orienteering.
Congratulations for finishing in such inclement conditions.
Buen camino!