Refresh page with video content

[royatkup]

I use the kiosk mode to render a video file (.mp4)
as well index.html as also the .mp4 file are stored local on the RPI

In the crontab I refer to a script which downloads a few times a day (in case it's updated) the mp4 file, this works great.
It also refreshes the website with the command:

DISPLAY=:0 xdotool key ctrl+R

Problem is, when we use the command like mentioned above, it keeps showing the same video.
Only after a reboot, or manual restart the chromium-browser it will show the new video.

I assume because the video is stored somewhere in the cache of the browser.
To resolve that, I have tried the following commands instead:

DISPLAY=:0 xdotool key ctrl+shift+R

and

DISPLAY=:0 xdotool key F5

With both commands you see the page is reloading, but it does not load the new video file.

Anybody have an idea?