The processid on the BPAWorkQueue table is for the Active Queue feature:
It does not necessarily mean that that is the only process that can alter items in the work queue. I wouldn't recommend using it as a method of reporting. I'd go with Jerin's response to finding which work queues have been worked on by which process.
I've had quite a bit of experience in building reports from the Blue Prism tables, feel free to PM me if you have issues getting the data you need.
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Nicholas Zejdlik
RPA Developer
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