Halsey used Bolton's facilities to get fit after recovering from cancer before making his comeback earlier this month.
Muamba went to salute the official after scoring in this month's 4-0 win over Wigan.
He said: "Mark has been a good friend of mine. Before the Wigan game he said if I score come and point to me.
"I'll do the same if I score against Manchester United.
"Mark's been through a lot. He's come back strong and I'm just glad he's recovered now. He's a great inspiration."