The data won't give it away, at least as long as the noise is sufficiently hidden with steganography and not just a mystery blob. But the tooling setup you use

The data won't give it away, at least as long as the noise is sufficiently hidden with steganography and not just a mystery blob. But the tooling setup you use to access the cleartext with your passphrase, without starting from first principles each time, that setup might very much give it away if the system comes under serious scrutiny. Note that there's a huge difference between "until proven guilty" and "until considered suspect": suddenly obscurity cannot be shrugged off at all, quite the opposite.