There must be a certain amount of trepidation about this visit, but presumably Her Majesty will send Joe a map so that aspect of the visit should be okay. Now Prince Philip has passed away there will be no entertaining remark about dodgy elections so that should be okay too. Looking good so far.
The Queen may make Joe seem a little lost and decrepit but he'll have his earpiece to tell him who she is so any awkwardness could be glossed over. Yes - it might work if we assume Joe lasts long enough.