Some Twitter Videos are not exposed by the API

Question

I noticed that in some cases, the video attached with the tweet is not accessible by using the REST API.

For example, this tweet clearly has video in it. however, this video is nowhere to be found when the tweet is retrieved from the API as shown below.

Is there an explanation for this?

Response from statuses/show with include_entities set to true:

{
   "created_at":"Sun Aug 27 05:03:27 +0000 2017",
   "id":901671478671769600,
   "id_str":"901671478671769600",
   "text":"\"I thought it was close. He's very composed. Fair play to @FloydMayweather.\" #ConorMcGregor @TheNotoriousMMA\u2026 https:\/\/t.co\/GqaK2rfCc8",
   "truncated":true,
   "entities":{
      "hashtags":[
         {
            "text":"ConorMcGregor",
            "indices":[
               77,
               91
            ]
         }
      ],
      "symbols":[

      ],
      "user_mentions":[
         {
            "screen_name":"FloydMayweather",
            "name":"Floyd Mayweather",
            "id":42519612,
            "id_str":"42519612",
            "indices":[
               58,
               74
            ]
         },
         {
            "screen_name":"TheNotoriousMMA",
            "name":"Conor McGregor",
            "id":369583954,
            "id_str":"369583954",
            "indices":[
               92,
               108
            ]
         }
      ],
      "urls":[
         {
            "url":"https:\/\/t.co\/GqaK2rfCc8",
            "expanded_url":"https:\/\/twitter.com\/i\/web\/status\/901671478671769600",
            "display_url":"twitter.com\/i\/web\/status\/9\u2026",
            "indices":[
               110,
               133
            ]
         }
      ]
   },
   "source":"\u003ca href=\"http:\/\/snappytv.com\" rel=\"nofollow\"\u003eSnappyTV.com\u003c\/a\u003e",
   "in_reply_to_status_id":null,
   "in_reply_to_status_id_str":null,
   "in_reply_to_user_id":null,
   "in_reply_to_user_id_str":null,
   "in_reply_to_screen_name":null,
   "user":{
      "id":6446742,
      "id_str":"6446742",
      "name":"UFC",
      "screen_name":"ufc",
      "location":"Worldwide",
      "description":"#MayweatherMcGregor | Sat. August 26 | LIVE on https:\/\/t.co\/Crf9DpHU3k",
      "url":"https:\/\/t.co\/a7DrIfLzyv",
      "entities":{
         "url":{
            "urls":[
               {
                  "url":"https:\/\/t.co\/a7DrIfLzyv",
                  "expanded_url":"http:\/\/bit.ly\/2oaqFfb",
                  "display_url":"bit.ly\/2oaqFfb",
                  "indices":[
                     0,
                     23
                  ]
               }
            ]
         },
         "description":{
            "urls":[
               {
                  "url":"https:\/\/t.co\/Crf9DpHU3k",
                  "expanded_url":"http:\/\/ufc.com\/order",
                  "display_url":"ufc.com\/order",
                  "indices":[
                     47,
                     70
                  ]
               }
            ]
         }
      },
      "protected":false,
      "followers_count":6157894,
      "friends_count":21053,
      "listed_count":13522,
      "created_at":"Wed May 30 16:11:00 +0000 2007",
      "favourites_count":17241,
      "utc_offset":-25200,
      "time_zone":"Pacific Time (US & Canada)",
      "geo_enabled":true,
      "verified":true,
      "statuses_count":80210,
      "lang":"en",
      "contributors_enabled":false,
      "is_translator":false,
      "is_translation_enabled":false,
      "profile_background_color":"000000",
      "profile_background_image_url":"http:\/\/pbs.twimg.com\/profile_background_images\/718558259867570176\/KrPdz61x.jpg",
      "profile_background_image_url_https":"https:\/\/pbs.twimg.com\/profile_background_images\/718558259867570176\/KrPdz61x.jpg",
      "profile_background_tile":false,
      "profile_image_url":"http:\/\/pbs.twimg.com\/profile_images\/622297337839288320\/h8h5fjmf_normal.png",
      "profile_image_url_https":"https:\/\/pbs.twimg.com\/profile_images\/622297337839288320\/h8h5fjmf_normal.png",
      "profile_banner_url":"https:\/\/pbs.twimg.com\/profile_banners\/6446742\/1503859206",
      "profile_link_color":"D91111",
      "profile_sidebar_border_color":"000000",
      "profile_sidebar_fill_color":"FAF5F5",
      "profile_text_color":"0F0F0F",
      "profile_use_background_image":true,
      "has_extended_profile":false,
      "default_profile":false,
      "default_profile_image":false,
      "following":false,
      "follow_request_sent":false,
      "notifications":false,
      "translator_type":"regular"
   },
   "geo":null,
   "coordinates":null,
   "place":null,
   "contributors":null,
   "is_quote_status":false,
   "retweet_count":4637,
   "favorite_count":10033,
   "favorited":false,
   "retweeted":false,
   "possibly_sensitive":false,
   "possibly_sensitive_appealable":false,
   "lang":"en"
}