Would Collagen Induction Therapy (Micro-needling) Be Helpful for Thick Lumpy Facelift Scar?

You are still early in the healing phase so the scar is still malleable. If it is already starting to become an unfavorable scar you need to get on it right away to prevent it from becoming a major problem. This is something your surgeon needs to get on top of right away. My personal opinion is microneedling will not help because it will stimulate collagen production and the problem is as you describe it over production of collagen.

The best bets in such cases are scar injections, medicated tape, scar massage (by hand or endermology) and pressure. Some doctors like silicone sheeting but my experience with it is underwhelming.

My response to your question/post does not represent formal medical advice or constitute a doctor patient relationship. You need to consult with i.e. personally see a board certified plastic surgeon in order to receive a formal evaluation and develop a doctor patient relationship.

We like Collagen Induction Therapy best for depressed (atrophic) scars.

You are describing rather thickened and wide scars. If you have hypertrophic scaring, localized steroid injections may be helpful in addition to apply silicone gel. If the scars are still unacceptable after treatment and waiting, revisional facelift with excision of the scars followed by meticulous closure is the best treatment.

This will probably not be helpful if the scars are wide. This is corrected by excising the scar and closing it withuot tension.