Did you notice that the other Tugger deposited their fixed week 52
online - Right now they seem to be totally lost at II, as demonstrated by the ridiculous answer they gave you.
When & where is your fixed week? If it is an event week/holiday week at a popular resort, you may still be able to rent it.
If you don't think it's a strong rental, then depositing it may still be possible.
Is it already registered (not deposited, but registered) with your II Acct.?
If your fixed week is in the next 60 days you would get a flex-change deposit that can only be used for reservations at 60 days out. However, within 60 days, it will still be a good exchanger. I got a 2 bdm. WPORV exchange for my Bro & SIL with a fixed SVR week that I deposited during flex-change.
Can you see your fixed week in your Acct. on the II website? If it's registered, you should be able to see it as an undeposited week. If you prefer/need to to deposit it, you could go online right now, and try to deposit it online. The worst that can happen is that they won't let you deposit it. If they do let you deposit it, you will know immediately.
As long as you get a deposit you can exchange with, you shouldn't worry about what happens to the week after you deposit it. At that point, it's II's problem.