Can they get sued if a crash is blamed on a bad map?
I doubt it, so long as it is sold as an uncertified VFR product.
Selling hardware+software is a gamble.
These people have been doing it for years, and have picked up a little market for themselves, but they won't be going anywhere now.
The problem is that cockpits are not that big and people are mostly looking for a "universal" solution.
The other thing is that anybody can buy, for peanuts, the complete 6-DVD set of the SRTM radar imagery, and write a visualiser prog which gives you 3D rendering of the flight path ahead. Every flight sim does it, and if you are not rendering silly stuff like water textures then you can do it on a smartphone... And it would sell, for say 50 quid. But not hundreds. One would do an Android version and an IOS version.