The Senate was in recess during those two appointmentss. The Senate is NOT currently in recess so these are NOT recess appointments and hence un-constitutional.
I really wish you were right, but sadly the Supreme Court disagrees with you. (Evans v. Stephans)
Currently there are no differences between an inter-session and intra-session recess in Congress. The second the gavel falls for people to go to lunch the President can install people.
Usually the sacrosanct amount of time passing was 10 days, however, there is no actual legal basis for that.
Since this particular title was already agreed to in Congress the President had the ability to fill the position.
To be honest this is probably a good thing for most of Congress, now they can go on their vacations without having to come back repeatedly just to try to block provisions they had already agreed upon.