If upon reveiwing all my loan documents I noticed that the lender failed to sign the deed in trust, does that make the transaction void?

Custom and practice in the real estate industry is that the borrower not the lender signs the trust deed to be recorded on the property being purchased. The trust deed secures the promissory note with respect to the loan that the borrower is receiving. The lender's name will be referenced in the trust deed that you are writing about. However, you are the one as the borrower who needs to sign it.