I am not sure what you refer to regarding the insurance. If the paperwork is in order they should release the money. Call Wells Fargo and ask them directly what is missing to try and clear up the reason they are not releasing the money.
Large banks can be difficult to deal with. Make sure you have completed the form and included all information. If the branch has its own form, use it. If you have siblings (so that others are also entitled to the property), then this will complicate the procedure -- all of you will have to sign the affidavit. Then ask for the branch manager, and keep going higher until you get resolution. If the bank refuses, then you will have to file a court petition to confirm your entitlement to the account, and obtain an order directing the bank to turn the funds over to you.
This general response is not intended to create an attorney-client relationship.
Contact Wells Fargo again; ask for a manager and either have them put in writing what they want from you or have them send you the documents you need to complete for them. If there are other heirs, they may need to sign off or give permission. This is legal information not legal advice.
If the holder of the decedent's property refuses to pay,
deliver, or transfer any personal property or evidence thereof to the
successor of the decedent within a reasonable time, the successor
may recover the property or compel its payment, delivery, or transfer
in an action brought for that purpose against the holder of the
property. If an action is brought against the holder under this
section, the court shall award reasonable attorney's fees to the
person or persons bringing the action if the court finds that the
holder of the decedent's property acted unreasonably in refusing to
pay, deliver, or transfer the property to them as required. If you need help doing this contact an attorney who should be able to asisst you and get the money to you ASAP.