Player Card Approval denied

Hi,
I was able to setup a twitter card for “summery below large image” and got it approved right away.

Then i tried to get a “player card” approved,but my requests for the player card got rejected by twitter and i can’t figure out why.

The twitter card validator gave me all those “green checkmarks” for the player card, so everything seemed to be right – still it gets rejected.
Twitter says the Reason for the rejection is that the video won’t play on Android devices (desktop and ios devices work).

I want to use player cards for all the posts that include an embedded youtube video link.

I tested that with the validator tool in chrome on an android device, and it’s true – the video won’t play.

I tried different versions of the youtube link in the jm twitter card meta box for the player url and stream url, but nothing was successful – so is this a bug or am i doing something wrong?

I used this version of the embedded link in the post:

https://www.youtube.com/embed/xxxxxxxxx?rel=0

and added the same url in the box for the iframe player and stream – this didn’t work.

Then i left the “stream” url blank – and used only the player url.
Then i left the “player” url blank – and used only the stream url.
then i tried the same combination but without the …?rel=0 at the end:

https://www.youtube.com/embed/xxxxxxxx

And i set the width and length in the meta box for the player card to 640×360 ..the same size that is set in the youtube iframe link:

…width=”640″ height=”360″ frameborder=”0″ allowfullscreen=”allowfullscreen”></iframe>..

or should i leave that blank in the meta-box settings?

what am i doing wrong? how can i fix this?
i used the same post to get the “summery card” approved – is this maybe the issue? do i have to use a new post to get the player card approved?

this is the link to the post i tried to get approved for a player card: link

something else i noticed: in the general settings for the jm twitter cards plugin – i can’t choose the player card as default card (it doesnt show up in the drop down menu)

and another question: what means this open “graph/seo yes/no” option in the settings? should i set it on yes or no? (i also use yoast’s wp-seo plugin – is this option only for people who dont use yoast’s seo plugin?)

https://wordpress.org/plugins/jm-twitter-cards/