I wonder if putting the video file on a server and then using an embedded link to the video file rather than storing it in the container would work since your using your own network.
You can test this by placing the video file on your server and then creating a new record and check the box to store only a reference to the file. The computer the video file is on will have to be available to all of your clients, of course.
You could also place the video as a hyperlink in a web page, think YouTube and a private account, and use the web viewer to show the video. You could host your own private pages etc.
I find that using Open URL works better than the Web Viewer on an iPhone. If you have a complete network path to the video file, you might try that in Open Url. If it works for you then you can use a text field to store the pathnames and use Open URL textfield.
Using software to create web pages you can insert a link to your video and open your web page in the web viewer by saving the url in a field.
Or some other option.
You might try using the Web Viewer to play the video in the container field.