I think it's more likely an Aulonocara var. 'rubescens'. The rubescens is believed to have been line bred from the stuartgranti 'maleri chidunga', but very well could have been hybridized with another species (A. jacobfreibergi 'otter point' is sometimes suggested as a possibility) to strengthen the red/orange. Rubescens have become a dime a dozen and I suspect are more likely to end up in an assorted cichlids shipment, whereas a true Aulonocara stuartgranti 'maleri chidunga', while not extremely rare, isn't something I'd expect to show up in an assorted shipment often.
WYite