ExtractTableNamesFromScript handling DDL statements unexpectedly

Given a script
```
BEGIN

CREATE TABLE `project1.dataset1.table1` AS
SELECT *
FROM `project2.dataset2.table2`;

CREATE TABLE `project3.dataset3.table3` (
foo STRING,
bar STRING
);

ALTER TABLE `project4.dataset4.table4`
ADD COLUMN IF NOT EXISTS foo STRING;

END;
```
I would expect `ExtractTableNamesFromScript` to parse out 4 tables:
* project1.dataset1.table1
* project2.dataset2.table2
* project3.dataset3.table3
* project4.dataset4.table4

but with the following options set
```
zetasql::LanguageOptions ConfigureLanguage() {
zetasql::LanguageOptions language_options =
zetasql::LanguageOptions::MaximumFeatures();
language_options.SetSupportsAllStatementKinds();
language_options.EnableLanguageFeature(zetasql::FEATURE_V_1_3_SCRIPT_LABEL);
return language_options;
}

zetasql::AnalyzerOptions ConfigureOptions() {
zetasql::LanguageOptions language_options = ConfigureLanguage();
zetasql::AnalyzerOptions analyzer_options(language_options);
return analyzer_options;
}
```
i.e. called with
```
zetasql::TableNamesSet table_names;
zetasql::AnalyzerOptions analyzer_options = ConfigureOptions();
absl::Status status =
zetasql::ExtractTableNamesFromScript(sproc, analyzer_options, &table_names);
```
`ExtractTableNamesFromScript` only identifies `project2.dataset2.table2`.

Is there a language option I'm missing? Or does this method handle top level DDL statements differently than any supporting nodes?