emailove
No, to what appear to be your assumption rather than something you have actually done in Premiere Elements. Let me explain why I am applying a No to the following which you wrote
The audio can show up in the track, without being in the Project Panel.
and then please let me know where I am misinterpreting what you wrote.
Source media are imported in a Premiere Elements project to the Project Media in versions earlier than 11 and to the Expert workspace Project Assets in Premiere Elements 11 and 12. And, it is not going to get to the Timeline until the user drags it there.
In Premiere Elements (any version) I have never seen "the audio can show up in the track without being in the Project Panel. If a file is in the Timeline, it has to be in the Project Media (earlier than 11) or Project Assets (11 and 12).
ATR