What if the inventory filed was provably incorrect by at least hundreds of thousands of dollars? How to prove criminal intent?

Even further, additional monies of +100K have entered the Estate and the inventory has not been amended. No estate taxes have been filed. Entire businesses and other assets were not listed. Meanwhile the CO-independent admiistrators' 'lawyer' (he has denied being the estate's lawyer!) has received $70K so far, jewelry and all other property is missing, and his son has received nothing. His sister (a Co-admin) has informed us in writing that it is ILLEGAL for him to even ask these questions until after the estate is settled - it has been 4.5 years. How do we prove fiduciary and legal breach and recover these totally undelineated legal fees (Lawyer has refiled same filings repeatedly, mostly saying 'this business or that business does not need to be appraised'? This looks like fraud