Objective morality would imply that there is innate value to life, which implies innate value to existence, even for matter. However it is even harder to explain why morality and meaning exist as concepts if they are illusions -- it implies all living things are delusional for valuing their own lives, which itself discredits the claimant.
Objective morality does not imply innate value to life in that you can claim an objective morality which does not value life, such as "life is inherently immoral, therefore the moral thing is to end life as much as possible".
Living things can be deluded in valuing their lives, when in fact their life has no value. This does not discredit a subjective morality.
The illusion of morality exists because natural selection enforced that behavior in human beings for better survival. A concept does not exist simply because natural selection determined that the belief it exists provides benefits to survival.
Meaning for existence doesn't follow from innate value for life, that's a distraction. One can value life, have a sense of right and wrong, and still not believe existence has any meaning.