I feel saddened by the loss of a supplier like this, however... realistically... you cannot close your business down, fail to communicate with people who have ordered from you, and expect that nothing will change. It's just not the way business is done. Customers need to know that if they order from a company they will get what they ordered when it was promised for delivery.
So while it is very sad to see this company go, it is not exactly a "sudden" death.
As for the involvement, or hint of involvement of some other company... it's best not to make unfounded accusations unless you are prepared to present facts. For example... did another company hold up shipments to them on purpose so J&C could not make shipping dates? Or did those other businesses tell customers who had been waiting for 6 months for undelivered product that they would supply it? There is a big difference.