Ended up getting the plus to try it out as I didn’t get any reply here.
So, to answer my own question, no it does not give you the possibility to set header image per post.
But found another way to do it, use the plugin “Unique Header”. You set the theme to not use featured images as header images, then you can use the plugin to set the header image on the post.
So as the rest of theme is working good, will be keeping it for now.
Hopefully the priority support is a bit faster than on here 😉