I believe both Ozium and Lysol kill mold spores, I have had good luck with Ozium, Remove cabin filter, set heat a/c blower on high and spray Ozium into cowl intake, Make sure tha a/c is NOT set to recirculate. Vary the heater setting for feet to dash to defrost. Then set the a/ to recirculate and spray into the bottom vents, the ones that blow heated air on your feet, they should be taking air in when the recirculate setting is used. Last, rep;ace the cabin filter, prefferably with on containing activated carbon.
I used 2 cans of Ozium and it worked for me. Avoid using recirculate as much as you can. It helps cause the mold problem.
PS Spray the carpet under the bottom heat vents.