Hi @Keith,
I am sorry as there is no other way to embed something from other source. You can also use <object>
and <embed>
but the results will be the same, i.e. you wont be able to edit the contents of the source. You can check the answer here
A bit advanced answer would be for you to get the video url and display it using html, but the source that you are using should give you the video url and permissions to access it. This is a bit tough as you need to know quite a bit about html5, server Post Messages, and even a bit of jQuery Plugin if you want to make video work in past browsers like old Internet Explorer version as well.
Hope I made the answer clear. Please feel free to ask again if this is not sufficiently described.
Regards,
Pratik