Only able to access NAS via WebAccess from LAN but not from WAN

[Dah4th]

Buffalo Hardware:
LinkStation 220 (LS220DE)
Firmware Version: 1.63-0.04
Two 4TB WD-Red HDD (RAID1 Configuration)

Computer:
Custom Build- Asus Mobo, i5 processor, 16GB RAM

Network:
ISP: AT&T U-Verse
Modem: 2Wire 3600HGV
Switch:  NETGEAR 10/100/1000 RJ-45 5-Port Gigabit Ethernet Switch
Router: Linksys-EA6300

I am not able access my NAS from any device unless that device is connected to my LAN. Typically this type of issue would point to a firewall issue so that's where I started.I completed the following T/S steps but was not able to pin point the root cause of my issue please help.

Troubleshooting:
* Registered my LinkStations WebAccess
* Selected a BuffaloNAS.com Name.
* Configured networking ports.
* Disabled Automatic Router Setup(UPnP) and set the ports as follows:
External Port: 2981
NAS Internal Port: 2981

* Accessed my modems interface and forwarded all traffic on to the LinkStation IP to port 2981.
***NOTE*** the above step was completed because the AT&T 2-wire modem is also a router.

* Accessed my routers interface and forwarded all traffic on to the LinkStation IP to port 2981.
* Using DCHP Reservations, I reserved the devices IP and MAC.
* Using www.canyouseeme.org, I checked to see if PORT 2981 was open but it was not.
* Soft rebooted all three devices. (Port still appeared closed)
* Called ISP AT&T and asked id pot 2981 was blocked "they said" it wasn't.

* Turned WebAccess off then on again. (No change)
* Changed my WebAccess Name. (No change)

I have exhausted every option that I can think of and am in need of direction. I want this to work so badly. A co-worker of mine (kind of a rival) said he tried to configure his Buffalo and was not able to so he returned it and got a Synology NAS. I want to 1-up him by getting my Buffalo to work  #EgoOnTheLine...Really I just want to beat this thing please help.