You are correct.
This is a relatively new feature with Mitel. You could alway call park on a console but not on a station. What you're describing is a classic "Orbit". At this point, I'd have to say I'm not even sure how to use the call park feature at the station level. You should be able to log into the 3300 and do a search on "call Park" in the help files and find what you need.
In general, we almost never install/train this feature. We actually have few hundred systems installed.
What we do is use the "remote hold retrieve" feature of the system. The way that works is you put the caller on hold and then do the page to pick up the call off of the line it's holding on. In our case the user would dial ##7<extn>. ##7 is the feature code we use for this. Yours would be different.
I hope this helps. If you need more, PM me and I'll put a little more time into getting your answer.
Ralph