He says they failed to make their case that this appeal will be the last.

他说，汽车制造厂家未成功说明这将是(他们的)最后一次请求。

youdao

However,their appeal failed.

VOA: special.2010.06.27

"I appeal once more to all the peoples involved, and to their political leaders, to recognise that confrontation has failed and will always fail, " he said.

CNN: Pope in Malta after peace plea