From what I recall, previous experiment elsewhere (Brazil?) showed that modified mosquitoes in fact transfer genes to native population, counter to assumptions. Was that sorted out or deemed not that big of a deal?
Unknown implications of the hybrid vigor and inadequate monitoring is still going on. We frankly do not know. We need to ask certain British companies working with the local governments in places where they tested OX513A. The last study implicates a 3% survival rate. At first the females discriminated against males with OX513A but the population quickly rebounded with a third hybrid that appears to be more "vigor" as the study indicated. Implications of this new hybrid is unknown.