Looks like adjusting inputLimits is what is suggested in https://forum.onlyoffice.com/t/the-file-size-exceeds-the-limitation-set-for-your-server/4888 as well. https://github.com/ONLYOFFICE/DocumentServer/issues/1674 and https://github.com/ONLYOFFICE/DocumentServer/issues/685 also suggests similar.
Just to double check, did you restart the app after making changes ?