Multiple Separators! How?
This doesn't sound like a Rules problem. (yet)
To re-state the issue: you are trying to output display the values, and use a delimiter when there are multiple values.  Correct?

If so, where is the display taking place, of for example, "Name1" / "Name2"
Is this in a Node, View, Module ... or elsewhere?  Please be as specific as possible.

A Rules problem would sound like "for Trigger X I expect Action Y to take place".