Choosing the Feed Meteor to Plant option compared to the Weird Edsel ending slashes the difficulty considerably because you don't have to deal with all the minutia of regaining New Kid menu access and skipping all those cutscenes at the end. I used the pool valve to re-enable New Kid here. The route I took to get here wasn't optimized for speed, just trying to figure it out slow with a ton of backtracking. Getting the timing right on feeding the plant is tough, but if you hit New Kid too early, you'll still have Meteor in your inventory and the meltdown timer is diffused.

It'd be something else to see some speedruns of this. I know you have it in you