What software is running inside these VMs? Bus sharing is usually only required when there is some OS-level clustering software being used, that‘s when multiple VMs would need access to a common virtual disk.
Can you provide screenshots/Error details while trying a vMotion of these VMs?
Can you confirm if the requirements mentioned in the following blog are being met? https://blogs.vmware.com/apps/2015/02/say-hello-vmotion-compatible-shared-disks-windows-clustering-vsphere.html