Several years ago, we got a BRM in the shop and we were very new to the PD injector issues. We had a dead miss on #3. As we had a brand-new injector, we thought we had little to lose by trying it. The BRM injectors are marked 'CL', but we installed one that said 'BA". It ran exactly in the numbers and we could find no fault with it's performance or economy.
The car went back to the owner. We didn't bother telling the difference in the injector. He's driving it still, with great effect.
I have several contacts whom I have discussed a myriad of PD injector issues. There is a consensus that Bosch makes a lot of numbers, but the truth is, they aren't that many sizes. Same thing concerning the two-stage injector bodies. They all basically do exactly the same thing. Some are shimmed different than others.
To the point, you can drive a BEW 100 injector to 150 hp rather easily. As long as you don't over-amp the ECU driver; good to go. The overlap for injector sizes appears to be quite large.
Bluntly, if you don't match injector number, but the results show good in block 13, what exactly is your concern? If the injector doesn't work, change it out. But as for a suggestion to replace all three, that's easy advice if you aren't paying the bill... $400 a pop is what appears to be the going rate... I'd rather think they are more like glow plugs... they either work or they don't. We've even seen rather large disparity in flow rate numbers without loss of economy.
As for how quickly injectors wear, we have documented 450,000 miles on some sets. 200,000 are too many to count. What's this about worn out at 100K? Whatever.... I think if the solenoid is doing it's job, the nozzle will do just fine. If the PD's can't make it 100k, I guess the CR's won't make it 50k?? Sounds like 'salesman' math to me.
Clean fuel is VERY important. However, as we recently posted, there are some issues that a .00001"-size microbe can foul injectors and I know of no filter that will stop that. The other problem issue that effects all injectors is the amount of biodiesel that is virtually mandated in some US states, to be mixed into the dino-diesel fuel, to the rate of up to 20%(Illinois and probably others). That is impending failure from varnishing. You can't filter glycerine from diesel fuel. The damage it does is more to the solenoid's operation then the injector. In that case, forget the nozzle, you'd need a new body.
my engine is TDI PD 85kw and my car has fault like your (blued) but in all cylinders, when my car is about on 1500rpm, values in 023 block, reaches and stops at +127ms and then appear the same faults in all cylinders PD Unit Injector: Cylinder 1,2,3,4 Regulation Range Exceeded (codes 17669, 17672, 17675 17678) and ASR light is appear, and in 018 block from 0 appear 47.0. The car kilometer is only 220 000km, so it could be all bad injectors 
