Ship manifests

I am searching for a ship manifest for my husband's grandmother.  I have searched Ancestry, Family Search, gjenvick, ggarchives, steve morse, immigrantships, and to no avail.  I have her passport papers to include a Certificate of Relevance, a Certificate of Good Conduct and Morality and a document from a doctor clearing her healthwise, all dated 18 Apr 1921 from Trieste, IT.  I also have a "Visa to Embark" card from the Port of Trieste dated 6 May 1921 as well as a "Second Class Landing" Ticket with a ship name of SS Presidente Wilson which was issued by the Trieste Company of Navigation. 

I did find one manifest for the Presidente Wilson, leaving Trieste of a passenger with her same name, but different age by 20 years but the destination and people in the US where she would be residing are totally different.   I am confident that this is not her, as this person arrived on 1 Jul 1921, and my person got married in Tacoma, WA on 6 Jul 1921.  I have also tried many variations of spelling for her name and many different arrival ports.  If anyone can offer some advice, I would be very grateful.  I'm thinking she got moved to a different ship but I just don't know.  Her information is below:

Ivanka or Ivana or Johanna Sankovich (Sankovic), born 1894 in Pasjak, Croatia.  Her parents were Antonius Sankovic and Anna Jurisevic.  She would have been 27 years old.

Her destination was Tacoma, WA.


Thanks so much! Denise Slosar