So, I called up CH to see if my order went through, and it doesn't even show up on thier computer system (even though it shows on CH.com as "pending").. apparently I'm not "entitled" to use the BOGO codes because only 1 code is assigned to my account or something like that.. I'm confused...

No, they're confused. This is quite common with CSR's. I suggest waiting a few days in hopes that it will clear up.

Technically it is true that only one code is assigned to your account. Each account has one sale offer assigned to it; they change every month or so.

However, we have discovered that certain sale offer codes DO work on most or all accounts. mpaul39 searches them out, as described in the A list of all offer codes thread stickied to the top of this forum.

The CSRs don't necessarily know about these "universal" sale offer codes. Why Columbia House even has them is unclear. I would guess that they are intended for certain short term mass mailing promotions; holiday weekend sales and the like. There also appear to be some that can be used at the CSR's discretion. The best ones, such as BOGOF are certainly much prized here! But you aren't supposed to "know" about them unless you have received one in a mailing/e-mail.