The Katie Johnson (pseudonym) case was initially dismissed on technical grounds but was then re-filed. It was supported by two witnesses statements, the most significant of which being from an eyewitness who claimed to have worked for Epstien and recruited underage girls for his parties. She claimed to have witness Trump rape Johnson on multiple occasions.
Johnson voluntarily withdrew the case. According to her lawyers, the withdrawal was due to Johnson receiving multiple death threats - presumably from those immediately in Trump or Epstien's orbit (since her identity was not public).
Given the independent witness testimony, I am particularly inclined to believe it. It is hard to imagine someone would open themselves up to the possibility of a huge defamation lawsuit by swearing that they had witnessed a rich and powerful man repeatedly rape a child. It is noteworthy that Trump (litigious as he is) never so much as threatened a defamation suit.
Ivana, as you note, also accused him of rape - in divorce proceedings - before later recanting (after she and Trump had entered into a settlement).
Jill Harth also accused Trump of attempted rape, and filed a suit back in 1997, which she says she was pressured into dropping. She has repeatedly stood by her accusations, though, and yet no defamation suit from Trump.
So 5 women (4 victims, 1 witness) have accused Trump of rape, or attempted rape, in court, under risk or perjury. 1 recanted after a hefty settlement which, one would likely assume, restrained her from repeating the allegation.
Gosh, what an unlucky, innocent man! Its a shame he simply doesnt have the time to sue any of these nasty slanderers.