In the government, there can be many types of scandals. Some, like Watergate, contain multiple incidents of legal violations made at the highest levels. Others should only be called scandal in quotes. The GSA conference overspending "scandal" appears to have been one of the latter.
One man who was fired as a result the scandal was restored to the position he was terminated from by a Merit Systems Protection Board (MSPB) judge who determined he had been wrongfully dismissed. The GSA Public Buildings Service Region 8 commissioner was fired over allegations of misconduct in the cost of a training conference held in Las Vegas in 2010.
The "scandal" erupted when news stories told of an $800,000 training conference for GSA employees in Las Vegas. The agency fired the commissioner, alleging he had approved "questionable and excessive expenditures," and that he had failed to stop, "impermissible spending and violations of various procurement laws."
The MSPB's administrative law judge found the GSA failed to produce evidence to support any of these charges. It is relativity clear that the commissioner was fired as a political scapegoat. While the spending at the conference may have been fairly high, the GSA failed to show where he violated any laws that warrant his termination.
Let's be honest, he was singled out for political reasons. Private business engages in "conferences" like this every day (without them, a significant percentage Las Vegas hotels would be shuttered). It was only because this was identified as "wasteful government spending" that it became an issue.
While it is fine to limit spending on this type of event, however, you cannot fire people without evidence of wrongdoing, merely to provide political cover for unflattering situations.
Source: Government executive: "MSPB exonerates Prouty for role in GSA's Western Regions Conference," Jason Miller, March 13, 2013