your ESXI has a static ip correct was the static ip provided by the ISP? or is fake? if it fake NAT your way to ISP address or else do the ESXI ip adress
now for the DD-WRT there are 2 options
Simple Version
Disable DHCP
Connect a LAN port to the main network / to the main Router's LAN port
Now you have an AccesPoint only setup, where clients are served IP details from your main network or main Router.
Long Version
Here's how to create a Wireless Access Point using dd-wrt v24.
Hard reset or 30/30/30 the router to dd-wrt default settings
Connect to the router @ http://192.168.1.1
Note: If this router is wired to another router, there may be conflicts (both
routers could have the same IP address). For the time being, disconnect this router from the main one.
Open the Setup -> Basic Setup tab
WAN Connection Type : Disabled
Local IP Address: 192.168.1.2 (i.e. different from primary router and out of primary router's DHCP pool)
Subnet Mask: 255.255.255.0 (i.e. same as primary router)
DHCP Server: Disable (also uncheck DNSmasq options)
(Recommended) Gateway/Local DNS: IP address of primary router (many things will fail without this as your router will not be able to access the internet or
another network without it)
(Optional) Assign WAN Port to Switch (visible only with WAN Connection Type set to disabled): Enable this if you want to use WAN port as a switch port
(Optional) NTP Client: Enable/Disable (if Enabled, specify Gateway/Local DNS above) Help
Save
Open the Setup -> Advanced Routing tab
(Optional) Change operating mode to: Router
Save
Open the Wireless -> Basic Settings tab
Wireless Network Name (SSID): YourNetworkNameHere
(Optional) Sensitivity Range: The max distance (in meters) to clients x2
Save
Open the Wireless -> Wireless Security tab
Note: Security is optional, but recommended! Clients must support whatever mode you select here.
(Recommended) Security Mode: WPA2
(Recommended) WPA Algorithm: AES
(Recommended) WPA Shared Key: >8 characters
Save
Open the Services -> Services tab
(Optional) DNSMasq: Disable (enable if you use additional DNSMasq settings)
(Optional) ttraff Daemon: Disable
Save
Open the Security -> Firewall tab
Uncheck all boxes except Filter Multicast
Save
Disable SPI firewall
Save
Open the Administration -> Management tab
(Recommended) Info Site Password Protection: Enable
(Recommended) Routing: Disabled (enable if you need to route between interfaces)
Apply Settings and connect Ethernet cable to main router via LAN-to-LAN uplink*
Reboot router to be sure all settings have been applied.
You may have to reboot your own PC or do "ipconfig /release" + "ipconfig /renew" from the Windows command line.