OK, first, if I were her I'd inquire of the SSA if she can get a caretaker spouse benefit due to caring for your child under 16. See here: https://www.ssa.gov/planners/disability/dfamily2.html
If your family maximum is 180% (as opposed to the 150% of some lowever incomed people), then your child is only getting 50% and there may be another 30% for your wife. She can collect this ongoing, as other eligible benefits arise due to age, and decide whether to switch later.
But to specifically answer your additional questions:
"If I die before she is 66 with a 10 year old in tow what will she get?" --------- She will still be eligible, as caretaker, and that rises to 75%, as does your child's benefit. But she is also now, at 66, eligible for a survivor widow benefit of 100%, so she will essentially get what you got, and your child will also be bumped up t 75% of that amount, until she is 18-19. Your wife will continue to get her 100% for her life, and it will not be dependent on caring for a child under 16.
If we divorce before or after she is 66? ---- If you were married more than 10 years, she can get a retirement spousal benefit of the 50% (just as if you were married) and when you die, same amount as noted above. If married less than 10 years, then she will only get that which caretaker of child would get, until child reaches 16.
Missing out on the grandfathering doesnt effect her because you indicate her own benefit is so small that it would not be a choice for her - she'd prefer 50% of yours, more than her own, even if hers grew by 32% to age 70 by her not collecting a spousal until then.
Given her close to retirement age, I am not seeing that new work will be such a big impact SS wise - if she will never be collecting on her own record anyway, and yours that she can collect on IS so big... it seems her spousal at 50% or her survivor benefit at 100%... all seems bigger and better choice than her own.