Naruto was dancing with her in his normal form, so he was definitely stronger.
Even without Kurama, he has Sage Mode which was practically equal to KCM against the 3rd RK, so he should still be a few cuts above her at full power.
That said, perhaps losing Kurama will have weakened his normal form due to how closely entangled they were and Delta may have received upgrades or adaptations. If so, then she could be stronger now.