No. No you cannot.
Zestful is designed to provide perks specific to the initiatives developed by your company - whether that be encouraging health and wellness, donating to charity, or fueling your grind with coffee. By allowing you to withdraw funds from Zestful, we would essentially be defeating that purpose. All Zestful funds must be spent through the Zestful perk cards.
Note: If you deposited your OWN funds into Zestful, on top of your employer benefits, then you can request to have those funds transferred back to your funding source. Simply contact support!