My problem is I don't have a way to directly test the embed. So I test by importing the mxf to PR - which shows the embed. Or looking at MediaInfo - which may not show the embed even if PR does.
> export as MXF and choose to embed as scc
Not really relevant to the embed issue (I don't think), but I'm not sure what you mean by that. The scc is a sidecar file format. It shows as greyed out when embedding, but I don't think it has anything to do with what is embedded. For example, NTSC caption stream 608, the default sidecar is .scc. For 708, the default is .mcc. So that is what shows if you embed.