Prevent "onchange" Event Conflict in JavaScript?

I have the below test javascript code which works:

var EmploymentStatusSelect = document.getElementById('mainForm:cont_appRequest_customers__0_employmentStatus:decoin:appRequest_customers__0_employmentStatus');
EmploymentStatusSelect.onchange = (event) => {
    var esSelVal = event.target.value;
    console.log(" event.target.value ==> " + event.target.value);
    if(esSelVal != ""){
        console.log("EmploymentStatusSelect ==> " + event.target.value);  
    } else {
       console.log("EmploymentStatusSelect will not report");
    }
}

The issue is it prevents the form on the page from functioning properly. There is existing logic on the web app for the onchange event in the form so when certain selections are made, the form dynamically displays other questions. When I introduce my code (above) , the existing dynamic field display breaks. Is there a way to rectify this in my code? I am injecting code via a tag management system so I can't touch the code on the page, I can only change my injected code. Is there a way to fix my code so it won't impact the other onchange logic?

Thanks!