How to get overwhelming smell of mildew out of a jacket? With an added complication!

[SuperBatFace]

So I bought a top shop camo jacket from eBay - it has a very large sequinned back (I intend to wear it to a Taylor Swift concert!)

It arrived today and my god. Overwhelming smell of mildew / fusty / very stale. It's really pretty bad

I took a chance (cos of the sequins) and put it in the machine on a handwash cycle - 20 degrees. With beads and a pod.

No. Still bad.

Tried again with washing powder and a wool cycle - hmm it's perhaps little better but still doesn't smell in any way fresh and clean.

Any tips of how to remove this stench? It smells of mold and mildew but it isn't moldy that I can see at all - it's clearly been stored in a bin bag in a shed or something for years!

Tip from costumiers - vodka in a spray bottle, give it a good spray inside and out, smell will go.

Years ago, I read a tip about putting mouldy-smelling things in a sealed bag with a banana (so the banana does not touch the things) and leaving them a few days. The banana will absorb the odour, apparently. Have never tried it so I don't know if it works.