The reason I said to just go and Change fuse 5 is b/c we see this all the time..the fuse looks fine, but the ends do not conduct ..and if that fuse circuit is open , the K38 Starter Interlock Relay does not allow starter activation..fitting your common complaint on that chassis.
So, change it , regardless of how you think it looks ...just to get that common problem off the table.

__________________
A Dalton