diff --git a/actions/instrument/workflow/main.sh b/actions/instrument/workflow/main.sh
index 358348c40a..e7312fff70 100644
--- a/actions/instrument/workflow/main.sh
+++ b/actions/instrument/workflow/main.sh
@@ -187,11 +187,10 @@ jq < "$jobs_json" -r --unbuffered '. | ["'"$TRACEPARENT"'", .id, .conclusion, .s
     export_deferred_signal_file() {
       file="$1"
       headers="$(mktemp)"
-      echo "$OTEL_EXPORTER_OTLP_HEADERS" >> "$headers"
       case "$file" in
-        *.logs) endpoint="${OTEL_EXPORTER_OTLP_LOGS_ENDPOINT:-${OTEL_EXPORTER_OTLP_ENDPOINT}/v1/logs}"; echo "$OTEL_EXPORTER_OTLP_LOGS_HEADERS" >> "$headers";;
-        *.metrics) endpoint="${OTEL_EXPORTER_OTLP_METRICS_ENDPOINT:-${OTEL_EXPORTER_OTLP_ENDPOINT}/v1/metrics}"; echo "$OTEL_EXPORTER_OTLP_METRICS_HEADERS" >> "$headers";;
-        *.traces) endpoint="${OTEL_EXPORTER_OTLP_TRACES_ENDPOINT:-${OTEL_EXPORTER_OTLP_ENDPOINT}/v1/traces}"; echo "$OTEL_EXPORTER_OTLP_TRACES_HEADERS" >> "$headers";;
+        *.logs) endpoint="${OTEL_EXPORTER_OTLP_LOGS_ENDPOINT:-${OTEL_EXPORTER_OTLP_ENDPOINT}/v1/logs}"; echo "$OTEL_EXPORTER_OTLP_HEADERS","$OTEL_EXPORTER_OTLP_LOGS_HEADERS" | tr ',' '\n' | grep -v '^$' | sed 's/=/: /g' >> "$headers";;
+        *.metrics) endpoint="${OTEL_EXPORTER_OTLP_METRICS_ENDPOINT:-${OTEL_EXPORTER_OTLP_ENDPOINT}/v1/metrics}"; echo "$OTEL_EXPORTER_OTLP_HEADERS","$OTEL_EXPORTER_OTLP_METRICS_HEADERS" | tr ',' '\n' | grep -v '^$' | sed 's/=/: /g' >> "$headers";;
+        *.traces) endpoint="${OTEL_EXPORTER_OTLP_TRACES_ENDPOINT:-${OTEL_EXPORTER_OTLP_ENDPOINT}/v1/traces}"; echo "$OTEL_EXPORTER_OTLP_HEADERS","$OTEL_EXPORTER_OTLP_TRACES_HEADERS" | tr ',' '\n' | grep -v '^$' | sed 's/=/: /g' >> "$headers";;
         *) return 1;;
       esac
       read -r content_type < "$file"