Having two accounts (profiles) may not help you with severe stat hacks.
Someone more knowledgeable than me please correct me if I am wrong about the following:
Stat hackers can set your level to negative or 0 and/or alter stats like kills, deaths, score, and experience to negative or 0; etc. When your level is 0 or negative, you cannot join multiplayer. When your kills, deaths, etc. are negative, you cannot join multiplayer.
I believe there are similar but more severe hacks that also affect your local data file in ways that alter inactive profiles (the ones you weren't using when you were hacked), preventing you from using those to join multiplayer or from creating a new profile.