It’s worth doing an overall check of the machine mechanically. Here’s an example of @WillAdams’ usual (and useful!) pointers.
If you feel you have gone through these steps correctly already, you might want to double check for any slop anywhere in the axis. With the machine powered on, grab the router collet (or tip of a large endmill) and try to move it around (gently) left/right/front/back/up/down, see if you can feel any slop in any direction. If you do, you should probably go back and re-check eccentrics and belt tension. Z-belt tension is a typically culprit, it’s easy to under-tension it.
My point about V bit angle is that sometimes, even though you select a 60° tool in Create, and insert a 60° bit in the router, the bit may in fact be actually slightly less or slightly more than 60° (say 59.5° or 60.5°). If you are using Carbide3D’s 60° bit (#302) that is unlikely, but cheap chinesium Vbits angles are sometimes all over the place.
The zeroing can be a bit tricky for Vbits that have a small flat at their tip, because whatever method you are using (paper or probe) will establish the zero upon contact of the flat part with the stock, while the CAD toolpath has probably assumed a very pointy VBit, and generated a toolpath for a Z0 that matches the pointy tip. Not sure I’m making sense, but my point is you may need to adjust Z0 a tiny bit (up or down) to compensate for that. Trial and error should tell you. But address the mechanical things first.
Finally, maybe share the feeds & speeds you used, for a check ? RPM, feedrate, plunge rate. It is possible that using too aggressive settings in hard wood and a less-than-perfectly-sharp Vbit results in too much forces being put on the axes. Ideally, you would want to try with a smaller depth per pass and see if that helps, but as far as I am aware Carbide Create does not allow to specify a max depth per pass.