We believe an employee has been doing real nasty things within the organisation.

We are collecting proofs at the moment.

I would like to get all the emails he has deleted and empty the bin for up to six months without the employee noticing it. For example a zip file with all the emails, sent to me or so. Confidentiality agreemts  allows us to do so and this is very serious matter. 

Would that be possible tecnically from zoho?