It’s possible it expired in the middle of the battle. If you are sure that it didn’t then you should send a support ticket to flare
One of the reasons that you didn’t receive the whole gold amount after the battle could be as AwesomestKnighest has mentioned:
Therefore, did you use a Gold Boost Token that ran out while you were fighting in the battle?
Or maybe his Treasure Chamber became full with only 1.5Million?
This is not possible, in this case it would show +0 gold when you get full.
I think this is because LokiLugotorix changed setup (a b c d) just before battle starts and the screen didn’t update itself. I can reproduce this when I switch from set A (gold bonus) to either b c d… It will still show 2M gold for example but in fact i’ll only get 500k.
I noticed many times that the gold shown is different before and after the battle, i think this is mainly because someone finished the battle earlier than you while you are still in the battle, so he/she took the gold first eventually you only taking the remaining gold.
Actually it’s always different, because the Matchmaker screen is not using the Alliance Gold boost on the formula.
But at the end, the total earned value already is.
I am not only saying for the 5.0 update. I know what you mean because the post battle screen applied all the gold bonus that the pre battle doesnt count.
And what you are saying the gold should be more at the post screen, not less.