D D Crow counter summoning conditions?

1. Can D D crow effect be activated to remove from play the machina fortress (about to be SP) AFTER monsters of up to lvl 8 is discarded into the graveyard as cost to special summon it???

2. Can D D crow be used to remove Ronintoadin AFTER it has removed another frog to SP itself from the graveyard???

Thanks for paying attention to my questions.

1) no because it does not start a chain

2) yes because removing a frog is a cost and you can respond to it.