Maintenance fees paid to foreign enterprises need to be withheld income tax, and the basic tax rate is 20%. According to international tax treaties, the specific tax rate varies from country to country, with the lowest 10%. Before remittance, you need to withhold and hand it over to the IRS to obtain the tax payment certificate, otherwise the SAFE will not agree to your remittance.
The second question is unclear. Do you need to withhold their taxes or do they need to go back to pay taxes?