He was a able to recognise the ten tails so that means it has to be kurama cause how else would he remember the 10 tails unless they always somehow remember day 1 when hagoromo split them and forget everything else
If we assume that this kurma has been inside hima since before the time skip, remembering that daemon sensed something powerful in her, then this ninetails has been around long enough to watch and observe and know what the ten tails are.
He was a able to recognise the ten tails so that means it has to be kurama cause how else would he remember the 10 tails unless they always somehow remember day 1 when hagoromo split them and forget everything else
If we assume that this kurma has been inside hima since before the time skip, remembering that daemon sensed something powerful in her, then this ninetails has been around long enough to watch and observe and know what the ten tails are.