Looking at that image and Streetview, there is only 1 lane for all traffic approaching the roundabout. It looks like you
may be able to squeeeze 2 cars side by side right at the entrance to the roundabout from where the OP has come from and so possibly have 2 lanes on the roundabout if people drive sensibly rather than "racing line".
What I'm having trouble with is:
indicate when it would be physically impossible to take first exit
Looks to be no reason why you can't take the first exit
the route taken does not allow excessive speed due to having to stop at entry
I'm going to assume (I know!) that we've stopped, the lorry was stopped and we're giving way to something that is taking what is our first exit and as it passes us signals left as I believe you should when exiting a roundabout (even if going straight on).
Therefore I don't see any issue with the lorry pulling out when it does.
My normal drive to/from the office involves a number of roundabouts where we get a mixture of cars waiting for a gap big enough to fit a Voyager in before pulling out to a roundabout where drivers of all types coming the other way are unwilling to stop unless they absolutely must.
I try, where possible, not to stop unless I absolutely have to - on some roads, that means a car in the outside lane flies past, comes to a halt and then overtakes me again shortly after the roundabout as having read the road ahead, I've been able to keep going - more fuel efficient and causing less wear on the brakes