Please help to take a look at the spectrum graph – what is causing the vibration?

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Our unit recently overhauled a twin-screw compressor, of the wet type. All bearings are rolling bearings. The male rotor has four teeth, while the female rotor has six teeth. The motor rotates at 3000 rpm; it drives the male rotor to move through a coupling, with the female rotor moving in response. The reason for the major repair was damage to the screw surface caused by the entry of foreign objects into the unit. After fusion welding, the rotor is shaped and dynamically balanced. All bearings have been replaced with new ones. After operation, the vertical vibration value at the coupling end of the rotor was relatively high (4.5 mm/s); alignment issues were not present, with the radial deviation being no more than 0.03 mm and the angular deviation being no more than 0.01 mm per 100 mm. From the spectrum graph, it is mainly the 200HZ frequency that is high. I have a question for everyone: Is this 200Hz frequency the meshing frequency? For a meshing twin-screw compressor like this (3000 rpm), should its fundamental frequency be 50HZ or 200HZ? Is the rotor imbalance manifested primarily at the rotation frequency of 50HZ or at the meshing frequency of 200HZ? Could everyone help figure out what is causing the vibration in the spectrum graph?