For deterministic attribution with a 100% match guarantee, device identifiers (AAID and IDFA) are a must.
If you see absolutely 0 install data coming through from your ad-partner integration, it's possible that you're not collecting Google Advertising ID (GAID/AAID) on Android or IDFA on iOS.
iOS: Add the AdSupport.framework.
Android: Add Google Play Services so that we can collect GAID.