You didn't specify the camera format, but either with DX or FF models, 38mm is fairly close to a normal angle of view. Thus any sense of exaggerated "perspective", or more precisely, geometric distortion, has to do with the relative spacing between elements inside the picture frame. Anything closer to the camera will be rendered larger, and objects close to the periphery can be perceived "stretched" as well as this lens is rectilinear. However, at the moderate wide setting you applied, the latter point shouldn't be of much concern.
To me the overall image looks pretty natural, and actually the different sizes of the people add to a feeling of "depth". Perhaps that was unintended and can only be rectified by having people at more similar distance to the camera plus shooting with a longer focal length.