"Andrew lived on one of the oldest working houseboats on the Thames, he was fiercely independent but madly in love with his wife, also a dialect coach, Gabrielle Rogers.
"Tragically she is stuck in quarantine in Australia, having just flown in from New Zealand last week.
"She was unable to see or talk to him at the end of his life and there is a chance a funeral may not be held."
Jack was "full of life", "funny, charming and a joy to be around", she added.
"He was still working full-pelt, currently coaching on the new Batman."
Jack's clients for his dialect coaching included the actors Robert Downey Junior and Chris Hemsworth.
His acting credits included The Last Jedi and the Force Awakens.