Echo-bot takes the lead, as main character.

Echo-Bot needs to gather evidence about Wormhole's evil schemes.

Do you remember Echo-Bot's core component, from the introduction? If not, look in its inventory.

Use the Vox Recorder on Wormhole to gather evidence.

You have to catch Wormhole having two conversations.

One conversation happens at the Universal Machine. The other happens outside when Wormhole is talking to Merkley. Use the Vox Recorder on Wormhole only when he is in those two locations.

Henry and Mum need the Vox Recorder. Somehow, Echo-Bot can just chuck it to them. Use the Vox Recorder on Henry and Mum.

Where would Wormhole throw things away? And how could you pop the bubble with a discarded item? (This is another puzzle which makes more sense in retrospect, in my opinion.)

Can you see anything that looks a bit like Echo-bot? There have been multiple clues (in game) about it, interestingly.

Interact with the Inconspicous Bin. Wormhole will throw an item into Echo-Bot.

Go to the ending sequence here.