Meetings between the principals after the events of the case do not in themselves present an issue of possible cover-up for trial; communications before the events of the case do not in themselves present an issue of conspiracy for trial, as the wrong was likely not planned in advance.
Judges shouldn't be asked to hunt for truffles.
http://media.ca1.uscourts.gov/pdf.opinions/17-2076U-01A.pdf
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.