Start bard. If you want to help then run up and help. If not then vicious mockery works well enough heroic tier and has a similar effect for what you are looking for. Get to at least level 5, 3rd level spells and short rest recovery bardic inspiration is important.

After you reach level 5 bard then consider rogue but I think you’ll find that there’s no good time to take the 3 levels of rogue. Getting your first lore spell is better at level 6. Getting 4th level spells at level 7. Getting the coveted 20 charisma at level 8 for more bardic inspiration. Getting 5th level spells at level 9. Getting the next lore spell at level 10.

Anyways, I don’t see a useful time to take the rogue levels before way later. Which generally means you shouldn’t worry at all about the multi class combination.