Getting the following logs from the docker container:
wsd-00026-00053 2018-11-22 17:36:11.045672 [ docbroker_005 ] ERR Cannot get file info from WOPI storage uri [https://nc.domain.com/apps/richdocuments/wopi/files/59572_ocxqc3gr3v6o?access_token=2mcS0atAQxZXjW25Be3rTmQexxAHHddO&access_token_ttl=0&permission=edit]. Error: Connection refused| wsd/Storage.cpp:446
wsd-00026-00053 2018-11-22 17:36:11.048893 [ docbroker_005 ] ERR Failed to add session to [/apps/richdocuments/wopi/files/59572_ocxqc3gr3v6o] with URI [https://nc.domain.com/apps/richdocuments/wopi/files/59572_ocxqc3gr3v6o?access_token=2mcS0atAQxZXjW25Be3rTmQexxAHHddO&access_token_ttl=0&permission=edit]: Connection refused| wsd/DocumentBroker.cpp:1041
wsd-00026-00053 2018-11-22 17:36:11.049298 [ docbroker_005 ] ERR Error while loading : Connection refused| wsd/LOOLWSD.cpp:2534
Searching around, I found it could be related to the docker container not resolving the ip address properly, in this case it needing to be the internal ip.