How record managers know which records are got deleted after the end of retention?

After retention period when document is going to delete disposition review will get start and document will get deleted. But after sometime if record manager(not admin) wanted to see that what documents were deleted in past is there any way? If I check in Microsoft Purview there i can see disposition history for a label. But how record manager can see that information without involving admin?

1. Are there any custom solutions available to achieve the same thing? 
2. Is it possible to collect signatures from the disposition reviewers? Either OOB or custom or third party integration.

Record manager: who can apply labels, participate in disposition review