MXF XDCAM HD50 1080i 59.94 frame rate

What you might be trying to do is 119.88 interlaced fields per second - which is completely nonstandard. No program will export what you call 59.94i in ANY video format. What everybody else, including the major companies, call "59.94i" is actually 29.97 fps, divided into 59.94 interlaced fields per second.

And the 59.94 fps time code is actually incorrect (or misinterpreted) for that video. This is because ALL NLEs actually deinterlace interlaced frames upon display for the purposes of editing. So, what you will see in the monitor is that every two consecutive frames are identical when you step frame-by-frame. That is a clear indication that your source video's frame rate is misinterpreted.

So, if you really want 59.94 fps, the only way that you can export with that frame rate is progressive (59.94p). However, the client may still reject the 59.94 fps progressive (deinterlaced) video. Faced with the client's situation, no one will have any choice but to reject the job request.