Let’s say a homeowner pays the original contractor in full, but said contractor failed to pay his subcontractor. You say no lien can be filed above. But could the subcontractor file a lien against the property owner anyway, even though they aren’t financial liable? Could a lien be used as a form of weaponizing the legal process to extort monetary concession from a homeowner that had already paid the original contractor in full? What prevents this something like this from happening?
Ohio law protects homeowners from the situation you describe. First, an owner may record an affidavit stating that the owner has paid the contractor in full for the work. Unless that statement is false, any lien perfected on the property by any subcontractor will be void if it was perfected after full payment was made.
Second, if the lienholder receives notice from an owner that the owner paid the general contractor in full before the owner received the mechanics' lien, the lienholder must release the lien within 30 days of that notice and its failure to do so may subject the lienholder to damages (including attorney fees).
If the subcontractor files a lien knowing that the owner has already paid the full contract sum to the general contractor, then the subcontractor could be liable for to the homeowner for damages, including for the homeowner's legal fees for getting rid of the lien. The homeowner also may have a claim for slander of title, which would include additional damages. In short, it's not a good idea for a subcontractor to try something like this.
Unfortunately, many homeowners don't know the law and may not be able to find the relevant statute easily (it is here: https://codes.ohio.gov/ohio-revised-code/section-1311.011), and are advised to hire an attorney. But as stated above, the subcontractor may be required to pay for that attorney. Hope this helps.
I'm not aware of a criminal statute this would easily apply to, but if a subcontractor does this repeatedly with the ill intent you describe, then it could violate consumer protection laws and be of interest to the Ohio Attorney General. At that point, and depending on the severity of the conduct, the behavior could become criminal.