Phil has no registered any businesses with KOGaming, Darksydephil, or DSPGaming in the name. The stuff you're saying about shares and sales tax is kind of nonsense.
Shares are irrelevant to business deductions and debt. You can't "throw shares" at a collector.
A $100 business purchase with $10 sales tax is a $110 write off, not a $10 deduction. And it's a reduction of his taxable income, not of his inome taxes.
I don't know where you got this information from.
As for personal liability, even if he has used a corporation to shield himself creditors can still till tap his ass. They can literally request a court order Networks/Twitch/Patreon give them the money instead of Phil. In another situation this could be the county sheriff literally emptying registers at a grocery store.