The tubing is thicker on an Alu frame.
MT60 is commonly given 122.5mm as the spacing to use, as the cranks have a low Q-factor (i.e very straight and low profile) otherwise the crank will/may contact the chainstay, and there's also the risk of a large outer chainring contacting the chainstay, either static or under load.
I've got a CAAD2 running low-Q cranks and it's very happy with a 110(!).
Currently running MT60's on a Zaskar with a 118mm and likewise on a Cadex CFM2 (that one's 73mm shell though). Have also run MT60's on a Saracen, a Carrera (both steel) and a Peugeot (alu) all with 115mm BB.
The CFM2 I can't run anything more than a 34T middle ring though, as the cranks are too far inboard, but I run that as a 1x9 anyway.
Tried the MT60's on a Giant MCM too, and that needed 122.5 as the cranks were otherwise hitting the chainstays.
I found 122.5 length waaay to flexy though, hence using 115/118 BB's on other bikes.
Given the tubing profiles on the Cannondale, I'd suggest 115 or 118mm should work, 110 really is a bit close!
The other thing to take into account is not just the BB fitment, but the pedal position - with a low-Q crankset, a short BB axle moves the pedals inboard too, definitely something to look at if using clipless pedals, but worth considering even when using flats. Depends whether you're a pedaller or a stomper, and hip/leg muscle use as well.
