Dammit, I hate RPM. Even now I’m starting to remember the ludicrously obscure command line options, I hate it. RPM is the single worst thing about Linux. My parents are not getting RedHat.
Specifically, if RPM can list the files in an .rpm, it damn well ought to be able to install them without hanging indefinitely. I ended up downloading the tar version and installing that over the top, to make sure all the files were there.
[Update: Known RedHat 8.0/RPM 4.x problem.]