Problem deleting Windows 10 Bootcamp partition

Hi everyone,

This seems to be a recurring issue, but I have yet find a solve for it that doesn't require a clean reinstall.

I am trying to delete my Windows 10 Bootcamp partition and recover the space it has taken so I can to extend my MacOS partition over the entire hard drive. In Boot Camp Assistant, the install or remove or Windows 8 or later is grayed out. I'm running High Sierra 10.13.2.

I have been in contact with Apple support and they suggest that I erase the Bootcamp partition via Disk Utilities and format it as APFS. But to be honest, the support person I chatted with had to do a lot of backround research and didn't sound particularly confident when they came up with this solution.

Before I do this, I wanted to see if anyone out there has had a similar problem as me and whether they have tried this solution or another to solve it. Here is my diskutil list, if that helps. Thanks.