Hypertrophic scars: will Halo laser flatten our the bumps? (Photos)

You would need to see an Experienced Dermatologist for this issue.  Halo is highly customizable, and you have a few different problems happening here.  I am unsure of your skin type, be sure you are seeing someone highly trained in laser resurfacing that fully understands and can educate you on the risks of pigmentation.  Best of luck to you!

Thank you for the photos and I am sorry that you have to experience this, these scars can be improved with a combination of vascular lasers like yellow laser, Aerolase, microneedling/prp, skin lightening, peels, and skin care. Sun protection is essential. I recommend getting a formal evaluation with an scarring expert. Silagen gel should be used twice daily with jan marini bioshield. Best, Dr. Emer

In my opinion, you do have some hypertrophic scars as well as depressed saucer and boxcars. Raised scars should be treated prior to laser surgery. Treatment can include injections with steroids, Verapamil, 5 fluorouracil or Hyaluronidase. Furthermore, these scars will need to be injected after laser treatment to prevent recurrence. The depressed scars should be raised prior to laser surgery. Lasers cannot lift scars. Remember that scars are treated based upon their type. With multiple types of scars, different methods and multiple sessions  will need to be employed. Find a scar expert. Ask to see photos.

I would want to use Platelet Rich plasma injected into each of the scars and then do the Halo and apply the PRP topically after creating at least 60 micron depth channels with the ablative laser. The new Halo software allows the practitioner to customize the settings for different areas so the raised scars may do better with more coverage and more ablation than the rest of the face. 
You will also want a strong growth factor serum like the keracell MD recuperate. Silagen would be helpful to apply after to keep the wound moist and help minimize reactive scarring.