The girlfriend has an '04 R53, and the dipstick broke off, and my genius self pushed it down past the curve trying to grab it with a grabber. This has me a bit on the concerned side. I've done some research, and it appears that there are two methods of action - 1, pull off the front of the car, and the radiator, and pull out the dipstick tube, or 2, drop the oil pan.

Now, neither of these are very appealing options. I hate working on this car. Period. And going to a shop isn't a very palatable option either, as anyone in the area who is willing to work on it will probably charge $600+ to do either one. The last work I wanted to farm out was replacing a rear caliper, which would have cost me over $400. I did it myself in an hour.

So, the question is this - what harm would come from just buying a new dipstick and shoving the old one into the oil pan? It's not dry sump, so it'd probably stay out of the crank and rods, it's too big to mess with the oil pump, and I can't see it decomposing...

 

I tried the grabber tool method you mentioned and I think that we had the same problem. If it passed the curve from the top then you have no option but to tear down the front of the car, trust me, this is the most effective way of extracting the tube...I have done this just two days ago. Looking at the Bentley repair manual, taking out the oil pan looks a bit tricky since taking out the screws that hold it to the block should be in sequence, no dice for me. Also, since the broken dipstick is lodged/stuck in the tube, there is another curve on it near the bottom, it will be in the tube and will not be accessible through the oil pan. Once extracted be sure to order a better dip stick just like what I bought from cravenspeed...well worth the money. I'm not affiliated with them but I saw this option from another forum.

I hope this helps.