Yes even if there is no physical sign of damage to the CU I would recommend to the insurance company the need to change the CU as a cost effective exercise?
There are several ways you can do this.
1) Quote specific regulations concerning RCD protection inside domestic dwellings such as 411.3.3 for Socket outlets and 522.6.101 for cable buried and that you need to conform to the regulations, that will blind them with science and insurance companies love a regulation.
2) Tell them as a competent person you can not guarantee what kind of damaged was sustained during the incident to the existing installation and in particular to the Consumer Unit and it is your considered opinion as that competent person it should be changed, they will not stick their necks out and over rule this, they may get a 2nd opinion who may want to say naw don't need it, well let him/she do that and take responsibility.
I'm pretty sure though that the combined baffling with science and putting the onus back on them will get what you want