They were desperate to get paid off before the election because they all figured Trump would lose the election and they wanted to cahs in while they still had the leverage of going public to hurt his election campaign.
Both are greedy, grasping losers so they reneged on their agreements so they could cash in on President Trump's status as President.
Trump actually was kind enough and released McDougal from her NDA and contract
Stormy Daniels just flat broke her agreement when she discovered that Never Trump operatives were wiling to pay big bucks to dirty Trump with her lies and grandstanding.
I think that it's reasonable to assume Trump may actually have been involved in some way with McDougal but Stormy Daniels is just flat out a lying extortionist with unlimited ambition.
Trump was intrigued with a porn star being cast on his show and he interviewed Daniels. She saw this as her big break to make the jump into mainstream entertainment but Trump gave the nod to Jenna Jameson, another porn star who is actually a very shrewd business lady who leveraged her porn career to become a very successful entrepreneur .
PUT DIRTY/ANGRY/LOSER MICHAEL COHEN into the mix for more entertainment.