Through atmospheric measurements, scientists have identified a chemical factory operated by Solvay in Southern Germany as the source of massive amounts of Sulfur Hexafluoride (SF₆) emissions. Being 24,000 times as bad as CO₂, SF₆ is the most potent known greenhouse gas.
So, in terms of how much they probably lied: really bad.
In terms of whether this one factory could significantly screw up climate: not as bad. Footprint is roughly the size of a large coal-burning plant going at full load.
They obviously have to fix their leaks + pay for their emissions + pay a large fine + show their internal documents to make it clear if this was intended.