That's why I showed you above the steps needed to force-install it. Flash player isn't officially supported anymore in Android OS, but as far as I know, it can still be installed the way described above. I don't have an Android device with me now, and I cannot verify. However, I do have an iPhone 6 and I see the same error. I wonder if embedding HTML5 links would fix the problem.
Edit:
By the way, did you try embedding the video manually inserting the BBCode [media] video [/media]?
Edit 2:
I did try to embed a video on my 4.0 installation and the iPhone played it without issue, while it will not play those clips in your forum. I think the problem might have more to do with forum/editor/bbcodes settings than flash or device settings at this point.