Vidzflow and embed code not working

Hello guys, i work on a client page and i added a video from vidzflow.
The support from vidzflow says, that everything is fine on their end.
When i load the page, the first Code / VIdeo isnt loading properly. Sometimes it shows up, but when i refresh the site its gone.

Can someone explain to me, if i am doing something wrong ? Is there a workaround ?
Its a website for a video-publisher, so i cant upload all the videos on the site, because of the page speed. That is why i tried vidzflow.

Is this maybe, because its not a paid plan yet? It should work, because i have a agency workspace plan, so custom code should work, even if the site isnt on a paid plan yet.

Best regards

Here is my site Read-Only: