Ok, after ready through carefully I am left with needing more info once you get the bike back in your possesion.
I say this because it sounds like the shop has your bike atm.
-I don't think one single fuse can take out the cluster and not bother anything else.
-The aux fuse box for your accessories is a very good move.
-It is true that HID ballasts are a big source of electrical noise and interference however I think you need to get a couple of other things checked first.
-You need to 100% verify that the cluster is plugged in.
- I think your other accessories will work fine once it gets connected to it's own source for power.
I think those were your two issues no?
Dead cluster and air ride and other accessories with the exception of the HID's) die after 10min of riding?
nosbig, you mentioned turn signals and tail lanps not working, was the OP having that issue too?