dict1 = {"test_cms_thing_network": {"status": {"passed"}}, "test_cms_thing_abstract": {"status": {"passed", "fail"}}}
dict2 = {"test_cms_thing_network": {"retry": 1}, "test_cms_thing_abstract": {"retry": 0}, "test_cms_thing_iotworks": {"retry": 1}}

merged_dict = {key: {**dict1.get(key, {}), **dict2.get(key, {})} for key in set(dict1) | set(dict2)}

print(merged_dict)