Sforno on Genesis 40:7/ספורנו על בראשית מ׳:ז׳

1סריסי פרעה אשר אתו במשמר בית אדוניו, seeing that his master had entrusted their well being to him, as we know from verse 4 “the official in charge appointed Joseph to be with them.” If it had not been for this, it would not have been appropriate for Joseph to enquire into the private affairs of these ministers awaiting their final sentence.