Whoever takes over will be hamstrung by relegation to L1.
Cardiff's revenues weren't amazing anyway, but TV money drops off significantly when you hit the third tier, plus you lose a % of bums on seats.
Also, starting this season, the FFP rules that allowed Birmingham and Wrexham to go wild with owner/investor equity have been tightened significantly:
https://www.bbc.co.uk/sport/football/articles/c36e4068113o
So, unless they find a way to quickly and significantly raise revenue, and/or fancy flouting FFP, there is no quick fix for them.
For a club that usually loves a quick fix, that's going to be a huge problem.