Combat Zone as Nexus

Just a quick question: can/will the VA use my time spent in a combat zone as a nexus to link my diagnosis and stressor? I submitted personal statements along with new evidence showing my treatment going back to 2023 after they initially denied my MH claim since I filed it secondary to OSA. In my supplemental I formally requested they re evaluate my claim and consider it primary caused by my deployment to Syria in 2018. I’m not really sure how else to link my issues to my deployment short or paying someone for a letter, any insight? In my denial letter they agreed I experienced an in service event and agreed with my diagnosis, not really sure how else to get this linked