pfSense voucher in Mikrotik

[nbctcp]

INFO
-Mikrotik RB951 as gateway
-pfSense as voucher generator in GUEST vlan

https://www.youtube.com/watch?v=XDNWBNb1l98
I want to combine Mikrotik with pfSense voucher
Basically I want like this
GUEST OPEN SSID only allow to go to Internet directly
before they surfing, guests have to authenticate through pfSense Captive Portal with generated voucher passcode

How to achieve that in Mikrotik
My theory I think in mikrotik, it should be blocked all guests ip in GUEST vlan except pfsense ip
All http/https traffic from GUEST vlan will be redirected by mikrotik to pfsense ip
I might be wrong

QUESTIONS:

1. anyone ever tried that
   tq