I doubt it. A trainmaster is usually over operating crews (engineers & conductors).
I know UP has a separate reporting structure for station agents, with agents at both Olgilvie and the outstations report to ticket office managers at Olgilvie, who eventually rolls up under the superintendent for commuter operations (who also has train operations).
It doesn't make sense for agents to report to a trainmaster because the issues you deal with for agents are entirely different -- there's cash management, ticket accounting, and I suppose some degree of overall responsibility of the station plant itself (platforms, signage, announcement systems).
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