Q.Blue Marlin Hibiscus
I set these sprouts out that I ordered with roots at least three weeks ago and they still have not sprouted. Can you tell if I need to wait or are they dead?

Dig a hole at least twice the size of the root mass on each of the dormant bare-root plants. Partially backfill the hole and position the root ball in the hole. Position the plant so the previous soil line will be even with ground level. (The stem/trunk will be darker in color below the original planting line and lighter in color above it). Once the plant is positioned at the proper planting depth, begin filling the hole with soil. Work the soil around the roots with your hands. When the hole is half filled, tamp the soil to remove any air pockets. Fill the planting hole with water and allow it to soak in. Straighten the plant in the hole and finish filling with soil. Leave a saucer-like depression around the stems to allow for moisture accumulation and retention. Water thoroughly after planting.
After 3 weeks the bare roots should be waking up, I would suggest contacting the seller.
https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/blue-hibiscus-information.htm