We have a similar issue: A multi-language project.
- Java which is build with ant and analyzed
- C++ which is build with msbuild and analyzed
The code interacts via JNI.
In Azure DevOps we build the two parts in parallel jobs (i.e. separate build servers).
Only one QualityGate is displayed and issues commented in the PR. On SonarQube server both parts are available.
I assume that the slower build deletes the report of the faster one.
Addition: In the summary tab of the build, both analyses are shown. Only in the PR there is only one reported.
Addition 2: Seems to be discussed and given to your dev team in this discussion