wow reaing your situation makes ME crazy !
my dog has coccidia once and it drove me crazy too, thinking "should i flip the house upside down and quarantine the whole place?!?!?!"
it drove me crazy and i thought i couldn't do it so i just gave up.
instead, i threw away all his toys, (which was heart breaking because they were some money), showered my dog, and washed the beddings (my bed as well since he sleeps there too).
and i hoped for the best.
2 weeks later after medication, i drop off the poop and i get an all clear and i was very very relieved.
i didn't step on my dog's poop and walk all over hte house though haha
anyways, i wish you luck. i feel your stress