I'm a flutist and my dad has a mkvii alto that I'm learning to play on. He has told me that there are some weird fingerings for it, but he can't remember what notes. He could be mistaken, but does anyone know of any fingerings that are weird and what alternate fingerings work for those notes?

I've never heard of this but maybe some very high notes need experimenting with.

I play a MK VII and I use regular fingerings.

Perhaps he is referring to the altisimo range which it is sometimes hard to find fingerings for.
A helpful hint for lower notes, if you find them gurgling or difficult to get out put a champagne cork in the bell, or your mouthpiece guard. On the low notes there is an air issue, something in the bell is just enough to fix it.