Back to the OP - yes, I would have no problem with Doria re-locating here. She seems to be a sensible, dignified lady, who understands the need for family privacy and she will not be a drain on the state as, presumably, the Royals will house her etc.. It will also be stabilising for Meghan to have her mum around during what must be a trying time as she adjusts.
The rest of the family are appalling i.m.o.p..