The correct & acceptable phrase to indicate that some papers are very likely to be accepted
Stating the status of manuscripts in a thesis should not be an issue. The best way is to phrase their status as expressed by the journal. We see this all the time from "submitted to", "under review in" to "revised with major/minor revision". You cannot state that they are likely to be accepted since that is not your decision and stranger things have happened. 

What has to be remembered is that even a paper that has been published can be discussed and criticised so the above information just means to an examiner that someone else, impartial, has possibly commented on the manuscript or that a journal has found it worthy of review. 

I would guess most examiners would see a status as additional "evidence" for a basic acceptable quality of the work but would not necessarily affect their judgement, which is personal anyway.