proved marriage VOID, "spouse" makes competing cla

Here is a brief run-down of the facts: My father died 12/2012. He made brother and I beneficiaries 2 months before he died. He didn't obtain the required spousal signature, (he lived in Texas, a CP state) , so insurance company puts everything on hold because Dad's death cert. stated he was married at the time he died and they contact the wife on record to allow her to claim as the spouse. After I made my claim to 50% of the policy as the beneficiary on record, I attacked the validity of any possible claim by the "spouse" on two fronts: That the policy was obtained in 1997, Dad married "spouse" in 2012 and Texas follows "inception of title" rule thus dad didn't need a spousal signature as the policy was his separate property, (it is a NON-ERISA group life policy). Then, while perusing Texas Family law and actually looking closely at my father's documents, I discovered that my father was still legally married to his PREVIOUS wife when he married this last one, thus making the last marriage VOID under Texas law. (The last wife and my father were separated in June 2012 and my father was trying to get the marriage declared void thru the courts. He died before it could be finalized) After I sent in all the documents to prove the marriage was void, including the paperwork from the court showing my father was trying to get the marriage declared void, the insurance company sent out a notice to the "spouse" that they were going to pay the listed beneficiaries because the marriage was void. However, they still gave her another chance to claim. The day after the deadline they gave her, she made a claim thru her lawyer declaring she can PROVE the marriage was valid. Now the claim is BACK in legal and I was told it would be another month for them to make a determination.
I provided the marriage certificate showing the April 10, 2012 marriage to last wife and also the divorce decree showing it was not finalized until August 14, 2012....4 MONTHS after the marriage to this last one.
I am getting worried because so much time has passed, bills are piling up and now my brother is giving up! He is refusing to obtain a lawyer and wants to let "God sort it out" I don't think it fair I risk MY 50% with a lawyer's 40% contingency fee and we win then BROTHER gets HIS full 50% and I get mine minus the 40%. I have threatened to make a claim for 100% of the proceeds if he doesn't respond in case this goes to interpleader, (NOT something I really want to do to strip him of his right, only to ensure the attorney fees are shared equally and not just by me)
WILL the insurance co. even consider the claim of a "punitive spouse" of less than 8 months as being a VALID claim on a life insurance policy that's been in effect for DECADES, (and she is not the beneficiary of)? IS a spouse's signature REQUIRED when a policy is NOT community Property? (I read the policy and NOTHING in there stated that the spouse MUST be the beneficiary....)
Can I, if this goes to interpleader, make a claim for my brother's portion if he defaults and doesn't respond? (so the contingency fee is taken from the TOTAL amount and not MY half only)
This nightmare has been going on since early January and I don't think I can mentally handle an interpleader lasting months or years.