Personally I can't see any problem whatsoever with being able to take a move-equivalent+a partial action in place of a standard action. Specifically because a partial action is defined as a standard action minus a move. The fact that the two add up to a standard action is easily demonstrated by the fact that it is possible to use a readied partial action plus a move-equivalent action.
I'd almost suspect that either someone forgot to write the line which states that move-equivalent+partial=standard, OR someone misworded the section of the rules which says you can't take partial actions unless something odd is happening.
Regardless, I hardly think that allowing someone to stand up and partial charge is breaking the game, or overpowering any one class.
Hence, either the GM has to be willing to be flexible in the face of sanity, and allow move-equivalent+partial action, OR he should be consistant, and allow the by-the-rules action of move-equivalent+ready with immedate trigger. Otherwise the GM is just being contrary.