tier 2 objectives for every event require you to complete all t1 objectives of that event. that is the definition of T2.
and when t3 crusaders come out one will have to complete all t1 and t2 objectives of the event.

I thought that might might be the case but I asked in hopes I missed something. Now the question is how do I get Idols faster?

There really is no "fastest way" to farm idols aside from the obvious. Free Play in "World's Wake" is a good place since the areas are easy and you can get pretty deep into the areas compared to other chapters. However, here's a few general tips...

1) Have a few saved formations. One should be a formation primarily focused around gold-finding. The more gold you get, the more levels you get, which means more DPS. Use the gold-find formation for as long as possible, meaning until you're not reasonably able to get to the next increment of 25 levels. You should never have to spend very long getting to the next 25. Once it slows down and starts taking a little long to reach the next 25, reset. More or less, once you stop insta-killing enemies, reset. Pushing another 10-15 areas won't make much of a difference, so the time is better spent starting a new run.

2) Eventually, you'll end up reaching far enough to hit the level cap (5000 without talents). Once that begins happening, do the same as above, but once you reach the level cap with all crusaders (shouldn't be too long after your DPSer reaches the cap), reset regardless of if you're still insta-killing. Since idols are based on levels, reaching more areas is just wasting time.

3) Invest in idol-buffing talents. There's a talent that increases idols based on which area you've reached in that run. If you've leveled that talent up, THEN you can keep continuing the run after reaching the cap, since progressing further will add idols. There's also a talent that increases idols based on how long you've been in that particular run, so the extra time spent progressing after the cap would also be helpful.

4) Regarding how to spend idols, prioritize talents that buff idol gain, but DO NOT obsess over them. They get very, very expensive, so level them up a few times within reason, but then start spreading your idols across other talents, too, to buff your DPS. It will take a long while to max out idol-buffing talents, so stockpiling idols just for them slows you down. Rather, the extra DPS will help you push further into areas, which will help gain more idols on reset anyway.

Specifically regarding the objectives/crusaders, don't worry about missing them now. They are on a yearly loop. If you can't get the crusaders right now, you'll have a chance to get them (and new ones) when the same event rolls around next year, and by then you'll be MUCH better-equipped to handle the objectives. And like Matthew said, event crusaders can be earned through missions before then, too, although they will be ungeared and borderline-useless. The upside is that if you get an event crusader from a mission, you don't have to do the "their objective" in the event, so you can just skip one or two objectives entirely.