Working in a team like this has taught me alot especially in the media industry, as we assigned everyone roles we'vre realised that if one person in unorganises the rest are unable to go on. However this dosent mean you should stop in your tracks of your production completely, it means you should take it upon urself to carry out and do the tasks required.
I am experienceing these types of diffriculties in my group at the moment but its shown me to only continue further even if things don't come out as expected and a member of the group shows very little intrest and barely any effort.
However the benefit of this is that because one member has no input you have to carry tasks between two and it makes it easier to organise and you can make sure things get done efficiently, simon and myself have been there on both filming days and edited all of the footage. It's a good team effort!