Tiktok already lost 200 million users since when India banned them from their country and now America is most likely to ban them as well so this is going to get nagative impact on the project and do you really think people spending time on Toktok ever thought about investing? 
It means the pump in dogecoin using this tiktok will not last long. And if some countries ban the tiktok then the dogecoin will dump again because tiktok will have a big impact to the users like dogecoin. Doing such strategy to pump a coin is a great idea but the problem is the result and the impact of it someday.