Congrats on your first GWJ jam!
The visual effect for the eating animation made it difficult to figure out the hitbox alongside the extra mechanic of needing to bump enemies with a shield first before consuming. Either making the hitbox the same size as the animation or adjusting the effect to be as small as the hitbox but still visible may have helped.
Since this game uses the unreliable narrator wild card, you could have the scientist also say something among the lines of "Don't use your shield when they approach you! They're friendly and just want to give you a hug. :)" This would help players figure out the consumption mechanics more quickly.
Don't stop practicing! :)