Hey, you've sponsored a conference – good for you!
Chances are good you wanted to help these folks out, and support some productive conversation, learning and networking. Chances are also pretty good you want to get some benefit out of the sponsorship yourself with goodwill and exposure.
And when they said you'd have an opportunity to speak to the participants, you jumped at it. And you have a great 15-minute pitch carefully crafted by the folks in marketing, including a PowerPoint video that hits all the key selling points.
So why do you have this nagging feeling of impending disaster?