I think I would talk to my spouse/partner and say that I saw the photographs of the party favors on his phone and would ask how it made him feel. I would say that I was uncomfortable with the unprofessional tone of the event, as his spouse, and would inquire as to whether other people in the office have been treated similarly.
I would not over-react but would handle it in a matter of fact fashion. I certainly would not talk to the manager about it as I wouldn’t want to do anything that might jeopardize my husband’s job. I also think my talking to the department manager would be as unprofessional as the party appears to have been. Unless you also work there, I just don’t think talking to the manager is the way to go.
If your husband was uncomfortable or indicates that he would be if they did it again, you might suggest that HE talk to the manager. If it didn’t bother him or he laughed it off, I certainly wouldn’t push it. I would let him know that it did make me feel a bit jealous (or whatever feeling/s you are having) just for the sake of open and honest communication in the relationship.
You can’t control how other people are going to behave, you can’t know that the behavior will be stopped. All you can do is express how it made YOU feel to your husband. Particularly as this event occurred so long ago, he may not understand why this is bothering you now, so you will probably have to explain that.
You can also turn this situation around and let him know that you want to meet him at home for lunch on his next birthday (with the appropriate wink) and let him know that you are the “real deal” and will ensure that he enjoys his birthday celebration with you. If I am not clear here, I am implying that you promise him a “quickie” or, better yet, suggest that you both take his birthday as a day off and that you will ensure he has a good time. Indicating that he can “have his cake and eat it too . . .”