The DNSMasq version used doesn't seem to accept any hostname/fqdn (pool.ntp.org, time.windows.com, time.nist.gov, etc) for option 42 (ntp server). IP addresses work fine, but obviously this is an issue. I have tried all manner of quotes and ways of specifying the option. Please test for yourself and let me know if it works… but I'm pretty sure it's a bug. I spent untold hours figuring out what was happening and then isolating it. I found this after my IP phones began failing to sync time. I believe this worked in at least one version of Tomato… but we've been using standard tomato for years in some cases so I can't be more specific.
Tomato Firmware v1.28.9049 MIPSR2-beta19 K26 USB vpn3.6