The card says:
"Choose your minion in play. Play a copy of that card from your hand as an extra minion"
If it would say "Choose your minion in play. Play a same named minion from your hand as an extra minion" then I would understand it better...
Though you may see a distinction here, a same-named minion is exactly the same as a copy of a minion.
But looking up what mitosis is (wiki), "Mitosis is the process, in the cell cycle, by which a cell duplicates into two genetically identical daughter cells."
The cards do what they say, without regard to the real world or language definitions. I can't use the Wikipedia description of Pluto to claim that a space exploration game plays differently.
A less facetious example: there's a giant eagle card for the The Lord of the Rings: The Card Game titled "Born Aloft." It should be "Borne Aloft" (the eagle lifts an ally from play back into your hand). Would you try to change the effect or wording of the card to match the title?
Smash Up is much more straightforward than people seem to think. 90% of all issues in my experience can be resolved with "Read the card. That's what happens."