Workplace wedding shower etiquette?

I work in a university setting and recently moved from a smaller department to a larger one.

My coworkers from the smaller department want to throw me a wedding shower, and asked for a list of who I want to invite. This has put me in between a rock and a hard place, because I’ve invited the entire small department (4 people) to my wedding and some of my new department (only the people I work closest to - about 5 people).

There are other colleagues across other departments who I would like to see at the shower, but I did not invite them to the wedding.

Is it rude for me/my coworkers to invite those people to my shower? Should I leave them off the list?

TIA!!