It is correct. Effectively, the Fenris Bike must Charge in order to gain the benefit of Secondary Attack; it cannot use this ability if it does not move.
If sing, sang, and sung, sink, sank, and sunk, and drink, drank, and drunk, how is it that it isn't bring, brang, and brung, think, thank and thunk, and ding, dang, and dung?
Don't even get me started about bad, badder and baddest. Run, ran AND run...again? C'mon!