Sorry to hear of your issue, but I'm confident that a 'lost crown' is replaceable/fixable.
I've had a crown fall out of a C11 Makaira Elite some years ago, fortunately it was whilst I was setting the time and I was able to catch it; but CW repaired it at no great expense.
You've not mentioned how you messaged CW but they have a
Service and Repairs page on their website; just click on the
"Request Service or Repair" box and follow the instruction / complete the on-line form.
From the tone of your post I take an inference that your C11 MSL has not been back to CW before and, with the repair to be effected and
age of the watch, I anticipate CW will recommend a 'Full Service'; be prepared.
I trust this is of help.
Guy
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