There’s no reason Kodak couldn’t invest in sensor development while keeping film production going - their expertise in colour and image processing would’ve given them a major advantage on the sensor market.
Nikon was never a film company so they make for a poor comparison anyway, their expertise is in lenses. Fujifilm is a more direct competitor and a better match, they pioneered digital cameras and diversified their business while still producing film and as a result are still worth 22b today.