She didn't punch them, she knocked them away with her arms, but still got burnt. And no, those explosive tags only blew off his frail zetsu arm and mask, because he absorbed part of the blast with Kamui. It didn't even do much damage to Konan either, so this shouldn't be used as means to prove why it'll do much against Tsunade. 20 paper bombs is nothing in front of Byakugou. Assuming Konans attacks are that strong (I would like to see the DB entries), Tsunade will always be capable of regenerating. She was cannonically bisected, and was still capable of not only enduring it, but recovering from it as well, granted Katsuyu. So this shouldn't be an issue either, assuming it even happens - which I doubt. And I really don't know how she'd ever get sufficated given her immense strength and chakra scalpal that should easily be able to rid any paper covering her mouth.