Doesn't "salvage" have to be documented and verified? I know the maritime
laws requires salvaged vessels to be fully documented.

Andrew... I think the devil is in the details in this case... If the guys drank a bottle of water/soda at the scene that was on the FedEx truck then arguably that would be larceny even though it would have to be destroyed (could not be sold) and the owners reimbursed by insurance... or perhaps the FFs took a piece of molten metal as a momento of "the big one"... maybe a charred FedEx logo... My guess is the "offense" was more in this nature - rather than a true "salvage" operation where something of value to the owner/insurance company was taken. I could be wrong and if any readers out there have better insight - please help us out - but that would be my guess based on what is publicly available. Now... if they did truly take someone of value from the scene - then the prosecutors are wrong for not prosecuting and the chief is wrong for refusing to deal with it. Again... I'm thinking its really a case of poor decisionmaking of a very minor nature... and maybe someone with a grudge who saw it...

I suspect you're right, although I can't think of anything I might find at a crash scene that would be worth even the remotest chance of a trip to the Graybar Hotel.
Of course, it would be a completely different story if the taken items had been turned over to the chief or law enforcement. I wish reporters these days knew how to ask questions, instead of just taking dictation.

Who and where was the on scene Incident Commander in all of this?

Obviously they had to establish a "Salvage Area" to place all of the recovered items out of the "Hot" zone, so Fed Ex could come in get them.

And, what is Mayor Rich Sykes doing, "Micro managing" his former Fire Chief's decision in a disciplinary matter, short of termination?

Too bad Chief Alan Bermensolo had to take the measures he did, but with the Mayor butting in, I can see why he did.

And, recruiting a New Chief may be a difficult thing because, anyone who takes the job, would always wonder if the Mayor will stick his nose in again, where it doesn't belong.

Best of luck in Chief Bermensolo's next Chiefs job.