Urgent help with installing Windows: I entered the wrong partition number

[Sethmex85]

I've been trying to follow the steps in this video "Install Windows on Mac without Boot Camp Assistant [NO USB OR CD]" on youtube [this portal is not letting me post Urls] and I'm stuck on the part where I'm asked to select a drive partition for installation (see attached Drives/Partitions).

Seems like the window partition drive isn't appearing (and none of the drive's are formattable except Drive 0 Partition 1). Reading through the comments under the video, I came to realize that I naively used partition "4" (in your video) and didn't bother to check my window partition number (which turns out to be 3). I already have 2 partitions (for SSD/Mac and Windows) set up on the disk utility.

I even tried to apply the respective commands with "3" in the terminal, but "VERR_ALREADY_EXISTS" popped up (see attached Terminal). I know the bootcamp.vmdk is already created, but I'm failing to find a way to remove the attachment, so that I could start over.

Any suggestions?