You don’t have to at all lol. There’s no rule!
Think you can mix, and a lot of it will come down to baby’s preferences!
My little girl had mam bottles and bibs dummies, she’s been fine mixing🥰
I think you will find that eventually the baby will reject what they don’t like. My son didn’t want any non MAM bottles and really liked the MAM dummies even though I offered him variety
Mine was fine with bottles but would never take any brand of dummy (even dipped in milk). It was a real pain at the time, but great not having to wean her off it later.
Yes I would so for example I have mam bottles and mam dummies, my first wouldn’t take any other dummy after he had got used to mam ones, so stick with the same aha x