Sure, it's possible if the 4th game ends before the 5th one begins. If these two games are overlapping then yes, I'd have a headache trying to figure it out too.

Now it depends on whether you've taken favorites or underdogs for legs 4 and 5.
If you've taken underdogs, I'd bet the favorite moneyline, to win about (guessing here) an eighth of what you'd win on the parlay?
Say a $100 parlay to win $2000.
Bet $500 on the 4th leg's fav with a -200 ML to win $250. Adjust the money depending on what the ML is, and as you feel comfortable with. If the favorite wins and covers you net $150 profit ($250 for the straight win - $100 for the parlay loss). If the dog wins outright then you've cut $500 off of your potential parlay winnings, but you're still in line to net $1500** profit. And if you get really lucky and the fav wins but doesn't cover, then you've won $250 on the straight bet AND your parlay for $2000** is still alive too.
If you've taken favorites then you'd have to hedge with a bet on the pointspread dog.
$100 parlay to win $2000.
Bet $550 on the dog to win $500. Dog covers and you are up $400 net. Fav covers and you're still alive for $1450** net profit from the parlay.
** = of course you won't get these amounts if you repeat the hedge on the 5th legs.