I managed to resolve my problems. While I was waiting to hear from IBM,
I did some research on Ant (an open source product used in the TSM
installer) and started looking at XML configuration files. I eventually
realized that all the installer was really supposed to do was to execute
two rpm commands: one with the '-e' option to remove any existing
license package, and the other with '-i' to install the new license
package. I executed the latter command manually.

When I tried to install the 6.2.2.0 TSM server I got errors similar to
those from the original attempt to install the license file. Executing
Linux commands myself was not a workable approach: the installation of
the TSM server itself and most of its prerequisites involved nothing
more than rpm commands, but the DB2 install was vastly more complex.

While I was waiting to hear from IBM I tried the server install again
with '-i console' rather the '-i silent' on the off chance of getting
better diagnostic messages. I did in fact get a useful message. The
installer needs, or thinks it needs, both 32 and 64 bit versions of
libstdc++.so.5 (the 'Server Installation Guide' only mentions
libstdc++.so.6, with no information on 32 bit versus 64 bit versions).
Once the system administrator installed the 32 bit version of the
older library, the server installation worked.