Biden's DOJ was deciding who to charge and with what. Under ALL past Presidents, the DOJ under the new President would finish the work started by the DOJ under Biden's administration. They were being thorough to try to make sure charge everyone that was involved in the criminal activities.
There is no law preventing the DOJ from releasing the files at any time. And obviously, the Trump DOJ has done nothing with them toward charging anyone. SO I don't think Trump ordered investigation of Clinton etc, to block their release. I think he is confident that the Senate will not pass the bill. I think he's hoping his DOJ can find something to charge Clinton etc. with. Based on everything that is known, they will fail to find anything on Clinton but could find something on Democratic donors.
But for those people who are so sure the files have been destroyed or "scrubbed" or whatever, this news of the Biden's DOJ investigation shows that will not work. There were obviously a bunch of people involved in the investigation, some of whom may still work for the DOJ and some who don't. But everyone who worked on that investigation knows what is in the files and likely could name many people they were prepared to charge. I'm confident that information will come out in some way sooner or later.