It looks to me that the pins or Q3, R2 and R3 all got hotter than the melting point. I'd start by removing R2 and R3, then testing their resistance. If you have to buy replacements, I'd definitely buy 2-3 of each (they are cheap) and include Q3. It will likely cost more in shipping than the parts themselves.

Are there any other pins on the backside that don't have the nice smooth look? i.e. that might have also melted recently? Possibly a part that has a heatsink on it?