Sending Mtgox code to bitinstant to receive money via paypal i personally dont think its a big deal and could be resolved within minutes, especially since the goxcode was already credited to bitinstant.
So my question right now is: Is my problem still worked on ( 4/8 and 4/9 lists or 4/8 and 4/10 not sure right now) or do i have to, again, submit my problem?
I have the same issue except my coupon was from BTC-E, but like you that part of the transaction was successful, it was just the PayPal side that had the issue. And I'm still waiting for mine to be fixed too... so much for simpler things getting fixed quicker, cause I don't think there's much simpler of a fix they could do than just sending us our money.