Since there is nothing i find causing such issue as of now, till we track down this issue, i will say if you find uploading via their site faster, use that and its fine. Just use IMG tags instead of inserting as Media=IMGUR
Your post image format is:
[MEDIA=imgur]a/rlfKbdv[/MEDIA]
How it should be like this usually to propely load on all devices with only image:
[IMG]https://i.imgur.com/BofZCq0.jpg[/IMG]
Imgur does provide this code on their website too. Follow this thread which has detailed tutorial:
How to post images on DDF