What I understand you to say.... PA.net has several servers.  one of the servers was blacklisted. 

How do I know which server my email is going thru? 

How come I am only missing email from one email address from one other email provider? This has been an ongoing issue - not off-and-on, but continual. 

How come I can send email to my brother but not receive it? 

How come I am not missing email from anywhere else? At least not that I am aware of.