It would have to be a dire mistake to result in a C+D. Aside from protecting trademarks, the violation would have to include wholesale copying of layouts and wordings before I think WotC would take the PR chance of issuing a C+D.
I thought they'd already done several in the past, with no major PR result. Someone correct me if I am incorrect on that. And honestly, if you try to take their current game using a back door, few are going to blame them for saying no. They are not quite so Big Bad Evil Corporation that taking their current baby is seen as ethically sound.
At least 99% of 5e could be sourced from exist OGC.
Numbers out of our butts make our arguments sound solid, without actually making them solid.
And that attention might result in a C+D but that doesn't mean it would result in a full lawsuit if someone had the money to force their hand.
If you have the money to force Hasbro's hand, what are you doing mucking about trying to publish 5e material?