Time to consult with a local elder law attorney with a probate practice because it's too late for the power of attorney, you'll have to go for a guardianship or conservatorship now... Lesson: Don't wait until it is too late
Consult with a local elder law attorney... generally payments made to family members will be treated as divestments and create a penalty period. Do not "guess" about this stuff, the consequences can be... severe!
It might be valid, but gosh, it sure does stink, doesn't it?
The question is whether there was "undue influence" and given the circumstances you describe, it seems to me that the burden of proof, proving that there was NO undue influence, would shift to the caregiver... You need to speak with an elder law attorney with experience in probate litigation asap!
Q: How can executor (family member/lawyer) of estate(s) maintain control of estate(s) in perpetuity?
A: By betraying the trust placed in him by his family. His ultimate destination is the first ring (Caina) of the Ninth Circle of Hell which is reserved for traitors to kin; frozen in ice, only their faces are exposed to be torn by demons.
Q: How do we proceed w/o his involvement?
A: Get to a good probate attorney and petition for guardianship and conservatorship. Then report this evil person...
Standing Orders in most courts have to do with routine matters dealt with in those courts... usually they are points of local procedure that respond to some local concern. That's why you need to seek counsel from a local attorney.