Trades and contracts being rescinded due to failed physicals is nothing new. No need for Silver to step in.
Donatas Motiejunas in 2016, 3-team trade vetoed
Luc Mbah a Moute in 2015, free agent contract voided
Chuck Hayes in 2011, free agent contract voided
Luther Head in 2010, free agent contract voided
Von Wafer in 2009, free agent contract voided
Tyson Chandler in 2009, trade for Chris Wilcox and Joe Smith vetoed
Cutino Mobley in 2008, trade went through because he was traded for salary cap reasons
Steven Hunter in 2006, trade for two 2nd rounders vetoed
Robert Traylor in 2005, free agent contract vetoed
Antoine Walker in 2005, renogtiated contract from 6 years guaranteed to 4
Shareef Abdur-Rahim in 2005, sign-and-trade to Nets vetoed
Mateen Cleaves in 2002, trade for Jumaine Jones vetoed
Alvin Williams in 2000, trade for Danny Fortson vetoed
Dino Radja in 1997, trade for Clarence Weatherspoon and Michael Cage vetoed
Victor Alexander in 1995, trade for Harold Minor vetoed
Duane Causwell in 1994, trade for Olden Polynice and David Wood vetoed.
Sean Elliot in 1994, trade for Robert Horry vetoed.
http://www.shamsports.com/2010/07/a-history-of-failed-physicals.htmlhttp://www.espn.com/nba/story/_/id/7370034/sacramento-kings-void-chuck-hayes-contract-failed-physicalhttps://www.sbnation.com/nba/2016/2/18/11049508/rockets-trade-donatas-motiejunas-marcus-thornton-to-pistonshttps://www.si.com/nba/2015/08/01/kings-luc-mbah-moute-contract-voided-nbpa-grievance