Your router was at 192.168.1.254 - what machine is .110?
FritzBox routers can be configured to not offer an IPv6 DNS server address to clients at all, see e.g. Unresolved ipv6 adress in my top list - #4 by Bucking_Horn.
But those IPv6 nameservers from your resolv.conf definitely didn't belong to your FritzBox, so it may be your Linksys equipment advertising those IPv6 addresses.
What's the purpose of that Linksys equipment anyway?