The video I linked is literally of Apollo.

Apollo has understood a bug to be a little critter he could potentially eat

How can you know that? He only knows a handful of words. The lizard probably looks more like a bug than like a cup or Wario. He’s familiar with the phrase “what’s this?” and “what made of?” If he had any real understanding, why didn’t he just ask those questions to expand his vocabulary?

I’m a big fan of Apollo, and he’s a lot of fun to watch, but his use of language is not demonstrative of a deeper understanding.

And regarding Koko:

Patterson reported that Koko invented new signs to communicate novel thoughts. For example, she said that nobody taught Koko the word for “ring”, so Koko combined the words “finger” and “bracelet”, hence “finger-bracelet”.[22][promotional source?] This type of claim was seen as a typical problem with Patterson’s methodology, as it relies on a human interpreter of Koko’s intentions.

Other researchers argued that Koko did not understand the meaning behind what she was doing and learned to complete the signs simply because the researchers rewarded her for doing so (indicating that her actions were the product of operant conditioning)