Yes I did watch him
No idea what role resolution looks like here so I can't answer that. Maybe I can ask host?
T-Pein said he bounces abilities back to the user and I am interpreting T-Peins claim as in anyone who visits him or his target, the visitors visiting him or the player T-Pein targets the visitors actions would get bounced back to them.
Mono said he tracked T-Pein and saw him visit Midnight so if I am understanding this right, T-Pein is supposed to make actions targeting Midnight bounce back to the original user and since Midnight said his action failed then T-Pein being a roleblocker would explain why Midnight's action failed.
In your scenario you said you watched T-Pein and if T-Pein visited Midnight then your action should go through on T-Pein and if T-Pein targeted himself and you targeted T-Pein then you would end up watching yourself.