Donkey Kong Country: Tropical Freeze 6-5: Forest Folly

I'm playing the Switch version of DKCTF and I'm completely stuck on 6-5. After the first checkpoint, I no matter what I do, Donkey Kong slides off the first grass platform before I can ground pound and send him to the next one. I've tried jumping, but that doesn't seem to help.

I've lost about 40 lives on this one section so far, and I have no idea what I'm supposed to be doing. When I watch videos of others playing the level online, this doesn't seem to be an issue.

Here's a video of the problem. What am I doing wrong?