Update @Kelheor: I fudged it--the parboiling part, that is.
I was having a conversation while cooking and then forgot about the noodles--left them in a little too long--tried to rescue them and ended up with curled sheets! So I ditched the duds and made the lasagna the regular way, but this time added a bit more room in the dish for extra sauce, adorned it with extra cashew ricotta, cooked it for a full hour (40 minutes under foil, 20 minutes topless, with a dish rotation in between), et voilĂ ! Taste-gasm.
Thanks again for the tips!