I would assume it would be Kosher. Guys on DXpeditions rack up QSOs with their stations while there.
So, what is the go with this situation? I have witnessed someone who worked a DX station while he was on (solo) DXpedition, and a few minutes later he worked the same station using his home call.
I have been on DXpedition working countries I had not worked before, and wished I could log them using my home call, but didn't as I believed it was wrong. It doesn't matter now, as there is worked pretty well everything that has been on in the past few years, so the temptation is no longer there.
A topic was discussed here a few months ago about operating from someone else's station using your own call and claiming the credit. This did not seem to infringe any legal requirements. I have worked stations on 160 m whom, I believe were using remote receivers, as the response was delayed several seconds.
Back to the topic; I have yet to work Norfolk I on 10 m, yet I was operating from Norfolk I on 10 m, working VK3s. Could I have remotely operated my home station via the Internet, from Norfolk I, and worked one of the guys with whom I was on DXpedition and claimed the credit?