The copy problem is also irrelevant for utilitarians, since all persons should be weighted equally under most utilitarian moral theories.

It's only an issue for self-interested actors. So, if spurs A and B both agree that A is C and B is C, that still doesn't help. Are the converse statements true? A selfish C will base their decisions on whether C is A.

I tend to view this as another nail in the coffin of ethical egoism. I lean toward just putting a certain value on each point in mind-space, with high value for human-like minds, and smaller or zero value on possible agents which don't pique our moral impulses.