Also joining are Andy Hockley as Monsieur Firmin, Martin Ball as Monsieur André, Jacinta Mulcahy as Madame Giry, Cat Lane as Meg Giry and Olivia Brereton and Harriet Jones, who will both play Christine at certain performances.
The production will continue to feature Sofia Escobar as Christine and Jeremy Secomb as Piangi.
Rauch recently finished playing Jean Valjean in Les Miserables in the West End, after previously playing the same role in the 25th anniversary production of Los Miserables in Barcelona. He has also played Feuilly and Marius in the show in his native Argentina, and appeared in the 25th anniversary celebration of the show at the O2 Arena.
Palmer, who has been seen in the West End in Crazy for You that transferred from the Open Air Theatre, Regent's Park, created the role of Prince Eric in The Little Mermaid on Broadway, and was also part of the original cast of Fosse. TV roles include Stanford Blatch's boyfriend Marcus in "Sex and the City."
Moore created the role of Ellen in the original cast of Miss Saigon. Other West End roles include appearing as both Fantine and Madame Thénardier in Les Misérables, Nancy in Oliver! and Anna in The King and I. She was recently seen in London Road at the National Theatre.
To book tickets, contact the box office on 0844 412 2707 or www.thephantomoftheopera.com.