Alright, this has been a fairly complicated one. I've came to the conclusion that
@OSRS Machines can not be held liable in this situation. They have refunded the initial order amount and will not be required to refund anything else.
There are multiple possible scenario's and it's impossible for us to know what happened. We do know that there were exactly 3 minutes and 14 seconds of time between the worker asking for
@finishmykcboss login info (via DM) and them showing a screenshot of the items missing:
https://i.imgur.com/teQ3Syc.png
In those 3 minutes and 14 seconds, the worker would've waited for the account info to be sent, log in to the account, enter the bank to grab a teleport close to the wilderness, get the account killed in the wilderness and then went to prif bank to re-log. This is a very short amount of time to do all that. On top of that, I've seen proof of the worker doing another order on an account with 3-4b bank value. They also could've taken value from the bank (1.9b bank left) which they didn't.
Another possibility is that this was faked by
@finishmykcboss. He could've lost these items in another way (other service provider, phishing link) or could've hid the items in a death storage location. This is by no means an accusation but it can't be ruled out either.
@finishmykcboss perhaps if you didn't drop trade (most of) the remaining value of the account I would've sided with you. I personally don't get how an ironman with a 2b bank value is considered 'ruined' because you lost some important items. It is of course your decision and I hope you won't regret it. I wish I could provide a better resolution to this report but unfortunately this is all I could do.