I have seen no evidence of any order given to Berthier from Napoleon to have bridges built at Leipzig.
I would suggest that it was discussed, but there was neither the time nor the material to build any bridges at all. Further, building the bridges would have given away Napoleon's withdrawal plans to the allies. Building bridges is a major engineering effort, especially in the middle of a major action.
And I don't see Berthier disobeying an order to do so. I can see him, as he was an engineer, even though he was a topographical engineer, telling Napoleon there wasn't time or material to complete the mission.
The mistake made was putting General Dulauloy in charge of the demolition of the bridge that was used.