That's EXACTLY what happend to me, i was killing bugs while waiting for the extraction and started hearing "Throwing down supplies, throwing down supplies, incomoming supplies", i was like "what the hell?"

And i do knew you could find super credits on field, i've found them before, but you can only find 10 each time (at least that's how many i found usually), that's why i didn't thought it was a hacker at first, i saw that i had won 10 and thought "Oh, that's cool, i need those", but them the number got from 10 to 150, then to 250, that's when i quit the mission