Correct filter usage/order for deinterlace 1920x540@50 to 1920x1080@25

[IcePlanet]

I have video with frame size 1920x540 in 50 fps. It is interlaced. My target is to create video 1920x1080 with 25 fps.

Have already done more than 100 experiments, but not happy with the result. The only good option is to use Merge Fields, but this is freezing avidemux for some videos (see my other topic). For this reason I'm searching for 'workaround'.

What is the best filter order when Merge fields is not possible to get 1920x1080@25fps?

My idea was to start with resize each frame to 1920x1080 (swsResize) and then change fps to 25 (ResampleFPS). The problem is that resulting video has visible interlacing artifacts.

Tried Yadif before/after ResampleFPS, tried  dgbob, Kernel deint, Libavdec... but can not find solution to produce picture of similar quality than original. Any ideas?

Attached is mediainfo or original file.

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[eumagga0x2a]

If the video is interlaced, the height of frames is bogus and the video is broken (some software has mistreated field-encoded video as progressive). The exactly right way to fix it is to apply Merge Fields, period.

What is generating such videos? It would be preferable by far to avoid them being created in the first place.