1. A computer-implemented method for managing sub-clusters within dependent clustered computing systems subsequent to partition events, at least a portion of the method being performed by a computing device comprising at least one processor, the method comprising: identifying a first computing cluster and a second computing cluster; determining that the first computing cluster comprises a virtual machine that is hosted by the second computing cluster such that the first computing cluster depends on the second computing cluster; detecting a partition event that partitions the first computing cluster into multiple sub-clusters that are unable to communicate with one another; determining, in response to detecting the partition event, whether the second computing cluster is partitioned into multiple sub-clusters; making, based at least in part on determining whether the second computing cluster is partitioned into multiple sub-clusters, a fencing decision for the multiple sub-clusters of the first computing cluster.