Can you quadruple check the motor and confirm you are using the correct function to activate rear washer. I'm not doubting your DIY but hose line is rarely the problem with this issue. I would do the following:
1) the front and rear windshields have identical motors so you can switch them out to verify the rear is not faulty assuming the front works already
2) rear washer is activated by pushing the stalk once and keeping it all the way back for a couple seconds
3) well if you have already done these checks here is the rear hose routing
http://www.realoem.com/bmw/enUS/show...diagId=61_1340
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