good idea but impossible
because you want html authentication
welcome page on controller lan port from to guest user, therefore you must use lan port untagged state on vlan 3 (guest vlan)and all guest user default gateway address must have controller lan port
my solution
lan port connect guest network on untagged state switch port, all guest user connect (guest vsc)directly guest network with default group vsc binding for vlan 3
vlan 3 dhcp server must be on msm controller
all access point login to controller on internet port on different vlan for example vlan 2 ,vlan2 dhcp services corpare dhcp server all access point ip address take corpare dhcp server for controller connection, all corpare user connect different vsc to different vlan with default group vcs binding.
very easy
only necessary you to understand device deployment architechture