blower fuse wiring fire

[miglenda]

Hello,
My blower fuse on our 300E 2.6 created a fire uder the hood. The insurance will cover repair but not the cause.
Athe moment the paint has been repaired(excellent match ect). They have wired the two main wires large 'pink and green' with other large wire colored 'Dark green and black',and have installed an in line 30 amp fuse.

The blower works well in at all speeds (settings) and this new fuse has not blown.

Questions:
#1. What caused it to get so hot that it started the hood liner and surounding wires to catch on fire? The car is as new and the motor compartment is also as new as in spotless.

#2. Orgininally these wire wher in a mercedes connector with the #2481 on it.
This connector has two male pins that when connected to the female side that has 2 small wirers one being yellow and black and the other small wire being brown.

The shop they sent it to to have the wiring repaired has done a very poor job and I am making an appointment with my adjuster to rectify this...BUT what type of fuse goes in this 'holder' (connecter} and what function do the small wires ( the yellow and black + the brown} that they have not reconnected???
perform?

I would truly appreciated others input on this. Thanks
kind regards
miglenda