This is a question to be asked to the said Company and to the poster himself.
Seven years before, he was found by the Company not suitable for their job hence the termination.
But what he did since then to improve his employability is a pertinent question to which the poster should have a positive answer with him. Performance is a relative aspect in employment easily influenced by many factors. One need not be an underperformer always. Experience in a different situation elsewhere and one's sincere efforts to self improvement may make a person more employable again on a job or in an organization from where he was sent out earlier on the ground of poor performance .