I don't personally play the mini-Steps anymore (due to lack of time) but I'm actually glad Party doesn't give a cashout option. Less players would play higher levels & longer to actually even have a game going especially at Step 5, I'd imagine?
It is the same parallel as getting a qualifier seat to a larger satellite but not able to cash out (i.e. Super Qualifier, Saturday qualifer, Sunday qualifer, 750K qualifier). It goes to your list of freerolls for future use. Of course, if an "event" expires, I don't know if Party gives out the cash equivalent or says "too bad".
Though, I have been reading about Stars's T$
"Tournament Dollars" as I didn't pay attention to it in the past. I realized this is one GREAT way to balance out the decision to "cash out from tournament qualifiers or SNG qualifiers" or to play out the expected tourney.
Of course, for Party Steps, it is an unique format & I think it's best to just play out your free entry(ies). Who knows, maybe you'll get into top 5 for any cash back, and since you have worked your way up, perhaps it means you can also reach the nice top 3 prizes for much lower risks (as in not plopping down $430 to begin with for a flat payout to top 5)?
Good luck,
* CalvinTy