Henderson had met City staff at the final home game of last season against Watford but now the Sky Blues will have to wait for any loan due to a change in managers at Sunderland.
Ricky Sbragia is still at Sunderland after stepping down from the first team manager's job and could help broker the deal to bring the winger back to the Ricoh Arena.
"The fact that they are getting a new manager changes the situation for us and it all depends on who comes in at Sunderland," said Chris Coleman to th CT.
"Had Ricky stayed in charge I was 99 per cent sure that we would have got Jordan back on loan next season but now we will have to wait and see.
"Sunderland won't want to do anything before they appoint a new manager but hopefully for us we are still in with a chance because it will be good if we can get him.
"We have got other targets of course, and we have got David Bell, whom we hope will come back fit and raring to go after his operation.
"We have got targets for the left wing and David can play on either side.
"But we can't wait forever and if other targets come up quicker then we will have to go ahead with them.
"We feel we would have had a better chance of getting Jordan had Ricky still been manager because he had said we could have him until January at least when he would have assessed things again.
"But he was pleased with the way he was coming along with us, nice and tidy, and hopefully the fact that he is still at the club will help.
"But we won't be the only ones in for him, although I know he enjoyed it down here so hopefully that might help as well."