When you use Set Data, it's asking for the Item ID which looks like this:
03d027e3-5f7f-4403-9557-ff7d277ebdbf.
There are a few actions that output the Item ID and it just depends on what you need but usually Get Next Item is what retrieves that and you use it later on to set the data. The value you have looks more like an Item Key which might be in a field inside the data and is used as the Item Key field when you view the queue from Control Room. That Item Key can't be used to set the data of a queue item and I would expect it to look something like what you have there.
Edit: I should stop looking at the forum late in the day. I re-read your post and realized what you were saying. Yeah the values look the same to me. Is this an issue you're able to reproduce where it says that the item key is different even though it looks exactly the same?
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Dave Morris
3Ci @ Southern Company
Atlanta, GA
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Dave Morris, 3Ci at Southern Company