With the sort of growth expectations you have, get actual legal advice. On the overall concept, consider that youtube-dl provides an unofficial (command-line)

With the sort of growth expectations you have, get actual legal advice. On the overall concept, consider that youtube-dl provides an unofficial (command-line) API to YouTube, and review the legal commentary in support of youtube-dl after its recent takedown at GitHub. But what's key is not really the legal part (as hyperpallium2 rightly pointed out) the terms of service and the risk of TikTok taking your company's oxygen away.