Hi there, I'm Tim and will be assisting you today. I have over 15 Years as an Engineer and have been with eBay, DoD and many others. I will do my VERY BEST to help you. If you like i can offer remote access and a call. In addition, with any positive rating I will support your question going forward for free.
Yeah, as far as i know there is no way to pass the start via PPT, BUT you can cut into a video mid stream and it should just play, or at any point. I did it as an example to a band i like (You will hate them!) to show you how it would work, if you think this is a good idea, just send me the URL for your video and I will do the same for you.
example below, we can cut in at any point, .05 seconds in, etc