Is $3,000 to seal basement floor to prevent moisture/mold a fair price?

My goal was to stop mold on items placed directly on the basement floor, which happened frequently before the sealant was applied. We spent $12k on mold remediation earlier this year. The basement was waterproofed in 2015 after flooding, but the floor slab wasn't addressed then. The problem is moisture/water vapor coming up from the floor, not liquid water. The basement has very high humidity; I empty three dehumidifiers twice a day. I'm concerned about mold potentially spreading upstairs. The issue seemed to get worse after we moved stuff out and removed the carpet, possibly making the floor colder. Based on feedback, I believe the product used was inappropriate for stopping water vapor because it is breathable.