I really doubt this is an injector problem. It is well known and documented that with the dry DPF's that the oil can become contaminated and the oil level rise. This is why over here every S40/V50/C30/C70 D5 has had a recall to reduce the oil level and a sticker placed by the dipstick to only fill to 3/4 full as MAX level.
What causes the excess fuel in the oil is the regen cycles. If you translate these symptoms to your car and problems I think it is blatantly obvious that your DPF is blocked and excess regen cycles being induced thus contaminating your oil with fuel?? This almost certainly will have nothing to do with injectors.
They really need to be changing the DPF or checking out the sensors to ensure that the sensors are not reporting in error that a regen is required. An ECU reload (software) may even help too just encase it is a software glitch of sorts causing the regens.
Good luck and fingers crossed you get sorted soon.
