I am not sure I am following the question or more specifically the assumption apparently being made here. It almost sounds like you may possibly have DNS being provided by a 3rd party DNS server confused with clustering which is not even remotely close to the same thing.
DNS standalone, master / slave, or as a clustered configuration which is basically, where the DNS server operates as both a master to the domains it serves as well as a slave replication server to the domains served by other DNS server members of the cluster, is all essentially the same and only really differs in how the DNS server is configured to operate.
In all of the above examples, you would need your DNS server still operating (whether that be BIND or NSD) else your domains would not be able to be resolved correctly. A clustered server still has to receive incoming zone transfers from a master server and likewise send out it's own notifies and zone updates to other cluster server members.
In the case of having all your domains handled by a 3rd party DNS server entirely where there is no slave mirroring and / or clustering involved then "no" you would not need a DNS server such as BIND running per say but I really would not recommend that sort of setup as you would create a substantial amount of extra work for you managing your domains.