I am afraid that without the key number replacement may be a problem, but either the dealer if bought from one or Bailey may be able to help. If on site possibly ask other owners to try theirs, as you never know you might be lucky. That apart it may need a locksmith to drill out the locks, although this might produce the number and save the other locks.
Our dealer had written our key number on the Welcome pack holder which might be worth checking if you have one.
Basically for safety we always carry two keys, one each, which hopefully gives us more security.
The lesson here for all of us might be to make sure you have the number written down somewhere safe.