The truth was that he didn't trust those two at all. If it were before, when the copy of his mind within Fenrir listened to only him, he could rest assured that the Loki up there would set everything aside to do his bidding.
But he wasn't the only one in control of his godheads anymore. That Gemini Supreme Metac pretending to be him was now the one in control.
Black Loki had been able to resist its influence when he was there to block it. But now that he was gone, the Gemini Supreme Metac would no longer be restricted and would focu on executing the mission the Gemini race and its god king gave him.
Since the Gemini Supreme Metac didn't know he existed, it had no reason to try to rescue him. The only reason it would do what he asked for and go back to the past would be to recover the Divine Spark for itself.
