My Grandpa has Alzheimer's, why won't VA/Tricare for life pay for a memory support home?

We recently had a not so fum run in with the VA. They sent a social worker to my grandparents home stating he was no longer capable of living in his home. While dealing with this on a Friday( in their ER) the best thing they could suggest is placing him in the psych ward, because they do not have an Alzeheimers support home. They gave us a list of VA approved home and with every fax and phone call,, as soon as you mention they are going through VA and have Tricare for life they immediately say he's in stage 3 and they won't take him, or they are not a memory support unit on lockdown. Why would the VA give you a liist like this if nobody will take him into their care? We ended up taking him to an approprite home, it's supposedly a VA accepted home, but now they refuse to pay for it. Isn't Tricare for life suppose to cover all his medical needs for life?? Any info you can give us would be so greatly appreciated. Confused in NE