Unlikely. More probable is that it will enhance the performance of the bacteria. Smaller oil particles or oil in solution are easier for bacteria to access.
The article has many errors of fact. A great many studies were done after Ixtoc, both in Mexico and in the US. Many of those can be found online. Ixtoc was not even close to being "the worst oil spill in history". Professor Patzek should be ashamed of making that statement. The worst spill was Gulf War I/Persian Gulf, which was a factor of ten worse than Ixtoc (and which also fully recovered).
Warm water helps the microorganisms, as compared to Alaska.