You may be right. They may find that the new stadium is a step too far. It is worth noting though that the interest rate on the bonds is quite low, and given that they are owned by fans, they may be able to get most of them to agree not to take repayment on the redemption date.
It's hard to fault the willingness of Wimbledon fans to get behind the club with money as well as with going to games.
The alternative to fan ownership isn't always bad. Brentford's trust managed to find an owner in Matthew Benham who is both a fan and willing not to take an immediate return. On the other hand, look at Notts County...…..
If things go bad at Plough Lane, they could then take another look at part private ownership. But I don't think they will go bad.