Bit confused here. You had 1.3m Madvertise requests and 100k Madvertise impressions. Where did the 1.2m requests go (I'm assuming 600k went to AdMob. How about the other 600k)?
Probably just unfilled. Before filling my remaining requests with House Ads, it was not unusual to only have a 50-75% fill rate on Admob. Maybe Madvertise is different (I've never used them) but it could be that no advert is served.
madvertise only fills in some european countries. In case madvertise doesn't fill, I use AdMob. For madvertise I use a 30 seconds refresh rate, for AdMob 60 seconds. This explains the differences.