Should I assume since I know what's causing the errors that DBD::mysql is safe to install and skip the make test stage?

Since you've done the 'make', you can write your own test script before the install, by including a 'use lib' statement to the directory you've built DBD::mysql in. E.g.:

use lib qw(
 /path/to/src/DBD-mysql.0.0.1/blib/lib
 /path/to/src/DBD-mysql.0.0.1/blib/arch
);
use DBI;
etc...
[download]

Those paths may not be exactly correct, of course... :-)