If this was a correlation study I could agree with you but more accurately I would instead posit that no hypothesis is confirmed. But this is a study about a deterministic mechanistic action.
We know that DMT binds with sigma-1 receptors (S1R) which is known to promote neurogenesis, such as fluvoxamine (in addition to many other SSRIs) in humans; we further know that the medication causes neurogenesis in humans, as do other medications with S1R affinity[0].
We then know that DMT does as well, we then measure that neurogenesis is observed in mice due to the same exact mechanism as SSRI's (i.e. medications with S1R affinity) in humans.
Perhaps at some point we should realize deterministic action in the context of the mammalian brain over human exceptionalism.