Anyone confusing the cross with anything Nazi is an idiot quite franky - but then I guess the world is full of idiots.
Clearly it isn't a swastika. Even if you confuse it with the German Iron Cross - this is a military medal dating from the Napoleonic Wars and, I assume, deriving from the Teutonic Knights.
The issue is no one knows what it is or why it was on the kit - this was debated at some length when the St Marks info first came out. Clearly it is either Templar Cross, Hospitaller Cross - or it's derivative/sister the Maltese Cross - or less likely a Teutonic Kinghts cross.
But all these entities were clearly Catholic, whereas St Marks Gorton was Protestant.
The best answer that has been put forward is that the kit was aquired as a job lot at a time when there was no money and they took what they could beg or borrow.