I guess the question I meant to ask was: In a world where your deontology would lead to horrible consequences, do you think it is likely for someone to come up with a totally different deontology that just happens to have good consequences most of the time in that world?

It seems likely indeed that someone would do that.

If an orphanage exploded every time someone did nothing in a moral dilemma

I think that in this case, one ought to go about getting the orphans into foster homes as quickly as possible.

One thing that's very complicated and not fully fleshed out that I didn't mention is that, in certain cases, one might be obliged to waive one's own rights, such that failing to do so is a contextually relevant wrong act and forfeits the rights anyway. It seems plausible that this could apply to cases where failing to waive some right will lead to an orphanage exploding.