Sync licenses. To fully avoid liability, you would need a sync and master use license, which we believe will be difficult and expensive for you to obtain. (We discuss master use and sync licenses in a previous entry.) You're correct; the odds favor you. It's unlikely the music publisher that owns rights to the song or the record label that owns rights to the sound recording will learn of your use (unless you're pitching a music-related startup). Those odds diminish if your animation/pitchdeck goes viral.
A "poor man's workaround"? You could pay for a corporate presentation performance license with BMI or ASCAP (whoever owns the rights). Though it won't satisfy the sync license requirement, it demonstrates your good will and may limit liability.
BTW Dept. (1) We don't agree that the music has no commercial use per se. Using music to excite investors seems like a commercial use to us. (2) The fact that others are posting the song at YouTube has no effect on your situation -- YouTube has its own methods of dealing with infringers.