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Yes, without the snubber, the ringing looks to be over 600V Vds when zoomed in.  So that may have damaged the IPW60R041P6 but I think body diode is still ok because it's still rectifying ok once the snubbers are in place.  I only ran very briefly without the snubbers so I could measure the ring frequency to calculate snubbers according to this https://www.ti.com/document-viewer/lit/html/SSZTBC7

This is another scope shot of both secondary Vds fets with no snubbers on longer timescale:

[ATTACH=full]193036[/ATTACH]

There is only one version of the transformer, they made 2 (of the same) samples which should match that datasheet AFAIK.