Thanks for creating this post. I know you added to check with the Hive-Engine discord to get the latest requirements. I figured I'd add them to my reply in case anyone comes across this in the near future. I started with 80GB but that filled up during the snapshot restore. I upgraded to 160GB. My node is currently running & synced with around 35GB free. Also, the latest snapshots can be found at https://snap.primersion.com/ Anyone setting up a witness node or even interested in setting one up, definitely check out the Hive-Engine discord. They're a very welcoming/helpful group.
RE: Step by Step Guide to setup Hive Engine Witness from scratch