Thats, several years after he left, but yes I heard it. He didn't make it to NYC until 1928. There is a pretty cool story of his first concert after he escaped USSR however...and it was the Tchaikovsky 1st as well, but it was in Berlin on a few hours notice
you've heard the story of Horwitz after he left the USSR. In his first concert he finished the Tchaikovsky concerto 3 bars ahead of the symphony.
Regarding the performance you are probably talking about, yes, he made his American debut at Carnegie Hall with the Tchaikovsky 1st in January '28. He and Rachmaninoff soon met and in fact played his 3rd concerto in the steinway basement with rachmaninoff himself accompanying with the orchestral part on a second piano. Thats pretty badass.