My fiancée and I sent out a check to the DJ for our upcoming wedding to fulfill our remaining debt to them of $600. We don't owe them this final payment for several months still, but we wanted to settle up early, since we had the ability to do so, and thought it would help reduce our stressors.
However now, three weeks after sending the check out, we noticed it hadn't been cashed, and asked the DJ about it. They claim it hasn't been received yet. Normally, I'd think the best solution would be to put a stop payment on the check, and pay them with an alternative check that we give them in an in-person meeting, to ensure it's not lost in the mail. The stop payment would cost $30. However, the check was mistakenly sent out without being signed, which I believe could render it invalid, or at the very least, refutable.
What are my options here, and are there any possible risks associated with them?