If vSphere replication is installed, it doesn’t matter if it’s a single vCenter or not. There are two problems with this:
1) if you run the fling against a VR protected VM, replication will be stopped by the fling (i.e. it will be redirected)
2) if you run the fling against a VM not protected by VR, the VR will prevent the fling from gathering traffic data
If you don’t have the VM protected, then you could, of course, protect it with VR and then configure the fling for it. This should be fine if you ignore the RPO violation errors from VR.
As for the ‘lwd’ or ‘remove’ missing option, my guess is that you password might contain special symbols, which need to be quoted?