There's no real "easy" way to OTK with Staunch Defender and Ojama Trio. If you're looking for them to smash into a Stone Statue of the Aztecs, get them into Attack position via Windstorm of Etaqua. If you have a high ATK power creature down, (2700 or more for OTK), Final Attack Orders, and possibly a weak creature (Spirit Reaper) they might attack so you can activate Staunch Defender, there's your time to activate Ojama Trio so that you can smash the heck out of him. Or if you only have the high attacker in your hand, but everything else, use A Hero Emerges (Hail Zombyra!) to special summon it, then when the replay attack occurs, active staunch defender, then activate Ojama Trio and watch your opponent throw a hissy fit from suddenly being suicided. Very situational combos though, that require a lot of cards.
Now looking at Amazoness Archers, when they attack an Amazoness of yours, activate Amazoness Archers, and chain Ojama Trio to it, the Trio resolves first, then Amazoness Archers resolves, forcing them and anything else on the opponent's field into attack position, forcing them to attack, and at a 500 ATK power loss. That alone can do some nice damage if they were killing your lone Amazoness Paladin with an 1850-1900 beatstick, or good ol' Berserk Gorilla.
If, and I say IF, because I'd like this confirmed, attacking the Amazoness counts at it beign targetted for purposes of activating Dramatic Rescue, you could also then activate it on the attack replay, and swap out your Amazoness for a huge ATK creature put in attack position, or a Stone Statue of the Aztecs in defense position and give them one heck of a smackdown. Still very situational, but being in an Amazoness theme deck, it'd be much easier to pull off this combo rather than trying the Staunch Defender version. If you're running Amazons anyway, you're gonna most likely be playing with 3 of each of the cards needed, making them much easier to have, and tossing in 3 Ojama Trios is great for a deck like that anyway, if to just have them ram into any Amazoness of yours with Amazoness Archers, or even as good bait to have them waste S/T removal on it. Dramatic Rescue would just make it easier to bait them into attacking for the switch, if indeed that would work.