Oh ya, heat will most certainly damage components over extended use. I wasnt aware that there was even a S/C designed for us that did not utilize the EGR. Seems to me that you would be doing nothing but staring at the big, ugly CEL the whole time.
Sounds like a good thing you fixed the fuel leak, cause who knows how long before that leak and that heat would turn your VX into a smoldering shell.
Has to be something you can do to resolve the EGR. I don't know that it is 100% of the problem but it certainly does have enough bearing on the heat issue. Really hard to say without being able to see this thing and get up in the guts of it.
Gary Noonan
'01 S/C VX / '18 Forester XT