My Magnolia 'Fairy Blush' is poorly, it has been declining pretty much from day 1 of planting which was two years ago. At first I thought it was just sulking, many plants sulk after being planted and I had no reason to believe that Fairy Blush was not just having a teenage moment and refusing to get out of bed.
Worried of Leicester
Dear Worried of Leicester
You have answered your own problem, you know you have other areas of the your garden that has more acid soil, so move the plant, yes, move it, its looks like it might not last where it is so what's to lose?
You have written as if you think the shrub is dying, so if it dies as a result of moving it you have lost nothing. If you move it and it improves then all will be well. It might be worth after moving it giving it a good feed, just to set it off on the right path.
Yours exasperated with answering self-evident problems