PORT 8080 FORWARDING IMPOSSIBILITY

I have a wireless IP camera. It says it MUST have use of port 8080 for it to function properly in order to view it off the net remotely or on my Android. I have a Linksys WRT1900AC router. I have already forwarded the port properly, however when I run a test the test result indicated that port 8080 is not reachable. I have temporarily removed McAfee Total Protection. I have verified that Windows firewall is not turned on. I have disconnected all computers and everything that uses the net in this home. However, with all this done I still get the message from a remote diagnostic / test site that 8080 is NOT reachable. It tells me that I should determine which other program or service is using that port. Now here is the REALLY odd thing. If I unplug my isp's radio, and unplug my router and switch so that they are not in the picture. Then I use a laptop with my Android cell acting as my ISP using PdaNet. I then check using Verizon's network and find that I STILL cannot connect to 8080! I am baffled. Can any expert out there "unbaffle" me? Note: I am NOT very knowledgable about  ports and networks, so please be understanding and if you offer ideas please be very clear in what you ask me to try. I want to be able to attempt implementing your suggestions exactly they way you want me to.  Additional: There is a site named www.portforward.com. They sell a guaranteed service promising to get any port to function for a person for $40.00. After 3 days they refunded my money saying they could not get it to work for them either. Quite a saga. Experts?