Configuring the Static NAT Mapping in CCA should work. How are you verifying if it works or not? Looking at the nat translations from your file, it appears the port forwarding is setup:
tcp 126.96.36.199:80 192.168.11.128:80 188.8.131.52:46420 184.108.40.206:46420
tcp 220.127.116.11:80 192.168.11.128:80 --- ---
This shows that the static translation is there and you have an existing translation sourced from 18.104.22.168.
If you run Wireshark on the inside server, do you see the requests coming in from 22.214.171.124?
Hope this helps.