Sadly NO, if this work on Poster, it will be really easy to maxed out the Survivors we have and that will be blocked by Devs on next patch. Just be patient for now because its really hard to get them aside resources are much easier to grind them.
Nope, you need to play as usual BUT all Chests in Shop are accessible from beginning. You can buy thousand chests without paying single gold, but ONLY Chests, everything else cant be bought free, you need to pay with currency to buy it.
Progression is still as usual, you need to grind daily Mission in order to upgrade your Account level (16 stars daily and thats it, no more additional atarts to grind) and unlock next mission by clearing the previous one.
You should be grateful that you already given infinite chests to unlock without paying single gold, dont ask too much or you will get bitten by them.