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launchpadboi
Middleburn tout the RO2 as a 'road' crank so not sure why it would be compatible with a 73mm bb* and even if it is, the bb shell width won't change the q factor**.
*Shimano make their HT2 mtb cranks compatible with either 68 or 73mm shells, you add spacers between the bb cups and shell to make up the difference, HT2 road cranks are 68mm only. The spindle is shorter and you fit no spacers between bb cups and shell.
**bb shell width has no bearing on crank position. Imagine square taper bb and cranks, a 68mm bb with 122mm axle puts the cranks at the same position from centreline as would a 73, 85 or even 100mm bb with 122mm axle. The only way you could get a wider q factor with the 'burns would be to fit a longer spindle. They are commonly photogrpahed with the spindle fitted in the nds crank but the picture below from the middleburn site shows they are separable and the following page lists different axles that are available - https://www.mountainbikecomponents.co.uk/product/rs8-x-0003-73-mm-2/. That shows a 138mm axle as being for fitting RS8 Xtype cranks into a 68/73mm shell. I'll leave it to you to research whether the RS8 and RO8 cranks share a spindle interface.