Helper classes also need the slf4j relocation treatment.
MODIFY
dd-java-agent/integrations/helpers/helpers.gradle
dd-java-agent/integrations/helpers/helpers.gradle
@@ -43,6 +43,8 @@ shadowJar {
classifier null
configurations = [project.configurations.compile]
+ relocate 'org.slf4j', 'dd.slf4j' // Prevents conflict with other SLF4J instances. Important for premain.
+
if (!project.hasProperty("disableShadowRelocate") || !disableShadowRelocate) {
// This is needed to align with the relocation of TraceResolver in dd-java-agent.
relocate 'io.opentracing.contrib', 'dd.opentracing.contrib'

Helper classes also need the slf4j relocation treatment.