3 TB Fusion Drive missing space after unsuccessful Windows installation via Bootcamp

Your 3.1 TB Fusion Drive isn't really missing space. Stopping the Windows install and trying to revert to a previous state inflated the size of the Recovery HD at the expense of your main macOS volume "Macintosh HD". The normal size of the Recovery HD partition is 650.0 MB with ~526 MB occupied by a base macOS system and ~124 MB of free space.

Now you can either remove the oversized recovery partition (alluding to this answer: How do I regain unaccessible free space after a failed Boot Camp install on a non-Fusion drive?), expand the Logical Volume disk2 and reinstall macOS to recreate the recovery partition or you can resize your current recovery partition to a smaller but non-standard size and expand the Logical Volume disk2.

The first option takes at least 90 minutes, the second probably less than two minutes.

The second option works like this:

• Boot to your main macOS volume
• Get the partition list with diskutil list and here the device identifier of the recovery partition

• Resize the oversized 1.5 TB recovery partition:

  diskutil resizeVolume diskXs3 1024m #with X either 0 or 1
  

  If you get a "too small" error choose a slightly larger size like 1088m until you are successful.

• Get the UUID of the Logical Volume with diskutil cs list

• Resize the CoreStorage stack with:

  diskutil cs resizeStack lvUUID size
  

  In your case that's:

  diskutil cs resizeStack ED2463F3-F297-4C53-88C7-6701DBF8E63E 3105817m
  

  If you get a "too large" error choose a slightly smaller size like 3105812m until you are successful. The larger your Recovery HD has to be in the first resize step, the smaller the size has to be here.