You can push Slimes in Spectator Mode (Whilest you should not be abled to do interact with them)
How to reproduce:
Create a creativeworld to test it and go into gamemode 3
1. Summon a slime (Make it easy for yourself and do /summon Slime ~ ~ ~ {Size:5} or just summon one with a spawnegg)
2. Try To Push It
3. You Push It
If still there is an image needed, or a mod or someone can ask me to add a picture. But I think it is a little useless, because this is clear enough
Confirmed