Please see the results of "bbb-conf --check" below. I used letsencrypt for my SSL certificate.
BigBlueButton Server 2.2.0-rc-5 (1685)
                    Kernel version: 4.4.0-1101-aws
                      Distribution: Ubuntu 16.04.6 LTS (64-bit)
                            Memory: 10399 MB
                         CPU cores: 4
/usr/share/bbb-web/WEB-INF/classes/bigbluebutton.properties (bbb-web)
       bigbluebutton.web.serverURL: 
https://webinar.search.org                defaultGuestPolicy: ALWAYS_ACCEPT
                 svgImagesRequired: true
/etc/nginx/sites-available/bigbluebutton (nginx)
                       server name: 
webinar.search.org                              port: 80, [::]:80
                    bbb-client dir: /var/www/bigbluebutton
/var/www/bigbluebutton/client/conf/config.xml (bbb-client)
                Port test (tunnel): rtmp://
webinar.search.org                              red5: 
webinar.search.org              useWebrtcIfAvailable: true
/opt/freeswitch/etc/freeswitch/vars.xml (FreeSWITCH)
                       local_ip_v4: 172.31.7.67
                   external_rtp_ip: 3.81.226.217
                   external_sip_ip: 3.81.226.217
/opt/freeswitch/etc/freeswitch/sip_profiles/external.xml (FreeSWITCH)
                        ext-rtp-ip: $${external_rtp_ip}
                        ext-sip-ip: $${external_sip_ip}
                        ws-binding: :5066
                       wss-binding: :7443
/usr/local/bigbluebutton/core/scripts/bigbluebutton.yml (record and playback)
                     playback_host: 
webinar.search.org                 playback_protocol: http
                            ffmpeg: 4.2.2-1bbb1~ubuntu16.04
/etc/bigbluebutton/nginx/sip.nginx (sip.nginx)
                        proxy_pass: 3.81.226.217
/usr/local/bigbluebutton/bbb-webrtc-sfu/config/default.yml (Kurento SFU)
                        kurento.ip: 172.31.7.67
                       kurento.url: ws://
127.0.0.1:8888/kurento                    localIpAddress: 172.31.7.67
               recordScreenSharing: true
                     recordWebcams: true
                  codec_video_main: VP8
               codec_video_content: VP8
/usr/share/meteor/bundle/programs/server/assets/app/config/settings.yml (HTML5 client)
                             build: 829
                        kurentoUrl: wss://
webinar.search.org/bbb-webrtc-sfu                  enableListenOnly: true
# Potential problems described below
# IP does not match:
#                           IP from ifconfig: 172.31.7.67
#   /etc/nginx/sites-available/bigbluebutton: 
webinar.search.org# Warning: API URL IPs do not match host:
#
#                                IP from ifconfig: 172.31.7.67
#  /var/lib/tomcat7/demo/bbb_api_conf.jsp: 
webinar.search.org# Warning: The setting of 3.81.226.217 for proxy_pass in
#
#    /etc/bigbluebutton/nginx/sip.nginx
#
# does not match the local IP address (172.31.7.67).
# (This is OK if you've manually changed the values)
# Warning: The API demos are installed and accessible from:
#
#    
https://webinar.search.org#
# and
#
#    
https://webinar.search.org/demo/demo1.jsp#
# These API demos allow anyone to access your server without authentication
# to create/manage meetings and recordings. They are for testing purposes only.
# If you are running a production system, remove them by running:
#
#    apt-get purge bbb-demo
# Warning: You have this server defined for https, but in
#
#   /etc/bigbluebutton/nginx/sip.nginx
#
#  did not find the use of https in definition for proxy_pass
#
#            proxy_pass 
http://3.81.226.217:5066;
#
# Warning: You have this server defined for https, but in
#
#   /etc/bigbluebutton/nginx/sip.nginx
#
#  did not find the use of port 7443 in definition for proxy_pass
#
#            proxy_pass 
http://3.81.226.217:5066;
#