A kill off would be awfully drastic, the damage is done.
Sonos want's their money per unit, they get that regardless of what HEOS does. Now Sonos wants fees and wilful damages too, rather than $40 a unit, that could add up to serious money and losses. And of course the bean counters look at when and where to right off losses.

HEOS has a lot invested and needs a streaming component. So they will most likely address changing the software, perhaps loosing features if they can't do it another way. Worst case, they'd walk away from the line, which would affect users future for software support and upgrades, but it will be cheaper to leave a couple engineers to support the line for a number of years rather than face a class action lawsuit.