They just made fun on the situation knowing that vast majority of Ukrainians hate Putin and they just made fun on the situation for thinking that US soldier is kneeling on Putin while the fact they are just fixing the carpet as part if diplomatic respect for Russian leader.

Here's the story about this if other people want to read about that situation https://timesofindia.indiatimes.com/world/us/us-soldiers-kneeling-for-putin-viral-red-carpet-photo-triggers-backlash-california-gov-newsom-calls-it-disgusting/articleshow/123328337.cms

But for sure US soldier won't do that as they are loyal to their flag and obey their leader.