You can do this electronically for any machine, but it will take a little work.
What you need is a off delay relay or module.
Something like this should work with a modification
https://www.ebay.com/itm/DC-12V-Adjustable-Signal-Trigger-Delay-Turn-Off-Delay-Timer-Switch-Relay-Module-/262662293474It sells for less than $5
Here is a quick drawing of a mod that should work.
You would have to connect it to the vend solenoid, and add 2 other things, 1 a 12v adapter to power it and a
ac relay to act as the trigger switch. That relay receives it's power from the vend solenoid. When it closes, it acts like a momentary switch to trigger the timer.
The timer is adjustable from 0 to 25 seconds.
The are other off delay relays, modules out there, some may be self contained.
As setup, deposit money to vend, vend solenoid triggers external timer relay closing contacts which triggers timer
Timer module relay controls machine light for set time, turning it on, which exceeds the momentary pulse to Vend solenoid