flopped weak flush...now what?

So, after a year long hiatus and only a couple of weeks after withdrawing most of my roll I've decided to get back to pokering and ran into this hand. after only 3 orbits of the table I've stacked MP1 once where he ran his gutshot into my aces and I lost most of it back to him after overplaying my AK into his Q2o on a 2K2 board . MP1 has pretty much been in every hand while MP2 seems to be a tight player that knows how to raise and fold. I'm attempting to open up my range in position as I've become a majour nit and figure I'd work on it now as opposed to higher stakes. This is FR BTW(can't seem to get converter working so here we go):

edit: forgot to mention the shortstack was just some random shorty that you always see on Everest.

schoefli19 is at MP1 with $17.48.
hitop78 is at MP2 with $17.36.
Trashcona is at BU with $10.33.

Trashcona dealt 6d7d

schoefli19 calls for $.10.
hitop78 raises $.35.
PhantomPhink folds.
Trashcona calls for $.45.
LuisGaster calls for $.40.
glmdmk folds.
schoefli19 calls for $.35.

The flop comes
4d 2d 5d.

LuisGaster checks.
schoefli19 bets $.20.
hitop78 calls for $.20.
Trashcona calls for $.20.
LuisGaster goes all-in for $3.74.
schoefli19 calls for $3.54.
hitop78 folds.

Trashcona ?

ALL IN.

How is this anything but allin? The only hand that beats is a higher flush, and you even have redraws to the nuts here.

AI!!!!!!!!!!! of course...

considering the open ended str8flush draw, i would not call it weak.

flopped a weak flush and an epic flush draw.

AI GAMBOOOOL

Ok, sounds good all. What if we change it up a bit and say on the same diamond flop as above we had something like AdKh, we were the preflop raiser and we c-bet and get reraised.

1-Do we push over the top of that as well?
2-What if our c-bet is min-raised?

Lets assume in this case it's a passive post flop fish.