The lubricant they would have used is a high temperature grease which is applied to the ears of the pads, where they touch the caliper. By insulating the caliper the pad is isolated, and when it vibrates there is no path for the noise to be transmitted (the vibration is what you hear as noise)

If they did it quickly, they may have just applied it from the outside with the pads installed. That fits with it washing off, which it shouldn't. You may want to try taking the calipers off and applying it properly.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
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