People in FL can be wrong or lied to, it has happened before. The cute Mario pills aren't pure MDMA though, they're MDMA cut with meth, coke, or heroin (prob fent these days) and pressed into pills, that's ecstasy. Pure molly looks like salt crystals but a little discolored, it's closer in appearance to meth (thus why meth is sold as molly to unsuspecting rubes), it's not a powder at all. Just because someone sold it as molly doesn't mean it is, see "meth."
Your friends were either lied to about what drug they were buying, or are lying to you hoping you'll believe it. If you search "what does molly mean in florida" you get the correct answer (mdma) from a bunch of lawyers telling you it is in fact not legal. Literally not even one r/drugs post or anything saying "what the fuck is wrong with florida calling every drug by another drug's name" or anything. Apparently slang terms for flakka are gravel, bath salts, cloud 9, and scarface (bath salts is the one I've heard) but not molly. Though it is structurally related to molly (methylenedioxymethamphetamine), bath salts are MDPV (methylenedioxypyrovalerone). Yes I had to google those spellings lmao.
I'm sorry, I'm just not gonna believe it's a widespread thing beyond one or two dummies you know unless I can find a single shred of evidence, one tweaker on a youtube video or errowid trip report or FL rapper calling flakka molly, anything beyond "totally bro it's the whole state of florida trust me bro."
That dude who put crack in the blunt didn't want to tell you it was crack, I absolutely guarantee it. Crack coincidentally can be smoked, can be wasted in a blunt (lose a lot but people do it all the time), does taste horrible, and smell kinda like burning plastic, and coke would make your mouth numb so I'm gonna guess crack will too, that was crack my friend.