I remember learning in yeshivah that if for example someone has guests the host is not allowed to have one level of kashrus for themselves and a lower one for guests.
For one thing that is rude as if to say “We are better then you so we get the higher kashrus”.
I do not remember learning about giving to someone else when neither party is eating it at that moment as in Shaloch Mannos but personally I would feel not very kind if I
went out and bought non Cholov Yisroael for someone else when I am strictly Cholov Yisroael for myself.
As far as it being “perfectly kosher” Well that is too big a machloikis to get into and I am not scholarly enough to discuss it, but even with the teshuvah that people use to quote Rav Feinstien, I have STILL heard from others who say it is still a machloikis.