Immigration certainly know the names, passport details, photos and finger prints of the over stayers. Run one query against their database and have the answer back in an hour ( depending on the computer system ). They probably have the query already programmed, with detailed breakdowns by country passport, number in Thailand, number authorized for 60 days, number over stayed based on 60 days, etc. etc.
As for foreigners owning businesses in Thailand, just go to the Ministry that registers the companies and directors, run a query against their database, and identify all directors without Thai Id numbers. Then go and visit the non-Thai directors, based on last location from immigration database. Of course a lot of data may not be up to date, and many small businesses may not be registered. But the database probably does contain the big fish, so fry the big ones first. Also fry the lawyers or consultants who assisted in establishing the nominee companies for foreigners. When one of these consultants is found, go through their files and bank accounts, to find other foreigners running companies.
Nothing complicated here. I am just wondering who is benefiting from not doing the work or who has been blocking the work?