From: Seoul, Korea
If you only pay 40% of what you promise, their happiness will decline. That's the most important nugget of information you've posted. If they had been fully remunerated, happiness would have gone up 4. The worker happiness mouseover doesn't give you the full picture.
The part in the Treasury/Cash Flow report where it says "Given" I think is also theoretical. If you had the coin, you'd have given them 696 credits. Check that same report at the bottom and see if you have a positive or negative balance. Also, check your cash at the top. If it's zero (or low) then there's your answer.
No doubt the mouseover information should be fixed. However, until that time, I would rely on the city reports to see if your workers are getting paid.
Beer, because barley makes lousy bread.