@ThomasAquinas it appears that you may want to spend a little more time reading the section: Firewall and IDS/IPS Evasion. They really do a great job of walking you through it. Also, pay attention to the hint in the question about them adding a new service which will be on a port.
Once you find out the new service, then think about which commands would you want to use on a single port. Also, if you read my original post on this topic, I think you will find all of this helpful.
Lastly, remember that nmap and netcat run differently as root than as a regular user. They also discuss this in the module. Try not to rush through the modules. I have to slow down and remember that it isn’t about completing the modules as much as it is about internalizing the information and developing the skills.