SPSS GENLINMIXED for non-nested structure

Dear experts, thank you for any help you might offer.
I have data in which the groupings are crossed, not nested. Each player responds to the same set of items.

In MIXED, I give a separate intercept to each player and to each item -- but not to each combination of these -- using two separate command lines

Now I want to do that in GENLINMIXED, and I can't see how. The DATA STRUCTURE option seems to require that the data is nested. As an experiment, I just ignored this and wrote the comparable two separate lines as above. But results not the same.

Is it possible to do this in GENLINMIXED? Any reason why it would be possible in MIXED but not in GENLINMIXED?

Thank you very much for any help at all!!