Executed the checklist from a previous post. Here are before and after picks of the absolutely filthy top. Ended up going at it with Krud Kutter, then a palm sander with WD-40, then razor blades. It is sealed using Minwax Paste Wax and is as smooth as glass.
These stains were caused by paint and primer used for preparing Warhammer miniatures:
I may have abused the garage lights to maximize shininess:
I still need to fabricate something to choke off the cabinet and force more dust through the vacuum hose. Also, the router table needs some work to make sure the melamine has all residue removed.