New OME Suspension fitted

[Henrivan]

I have just (yesterday) had OME suspension fitted for my 2012 Pajero DID 2 door.
Problem is, the front lift is 2cm higher than the rear lift after work was done.
Measured from the bottom of the wheel rim to the top of the mudguard body; front = 80cm and back = 78cm
The fitment was done as per the OME catalogue;
OME 2915 spring /
OME 90006 Sport strut
OME 2994 spring /
OME 60033 sport shock.

They have now suggested that we refit with another front shock to get the lift level right (I think the propose to fit the petrol suspension in front to level it out? I have to go back today.
Please let me have your advise / input on this. This very technical for me (and outcome does not make sense).
Many thanks