Is there grounds for a lawsuit if I was accused of abuse and Vindicated by Child Protective Services.

Need more facts. Did other parent concoct story? What was source of lie?

What route should I take to prevent my kids from having to return to a home where they are being neglected by their custodial?

File for child custody (either ex parte or on regular calendar).

Does the court mean American mothers day on Sunday May 8th or Mexican mothers day Tuesday May 10th

I concur. If you want Mexican Mother's Day, request it along with any other foreign holidays you want.

No. The Court determines what the issues are and what your time estimate is for trial.

Can my mother in law take our kids if my wife goes to jail ?

She may file for guardianship of the children. However, the outcome depends on your relationship with the children and your living environment.

Can she obtain a restraining order against me from seeing my grandchildren when my son allows me to see them?

See your grandchildren during his custodial time.

See above

If you are caring for the kids &/or smoking marijuana around them, your living there is not key.

How do I stop the harassment from a grand/parent and can it be permanent? What should i provide to the court for the trial?

You need to file a Civil Harassment request.

Es husband will not comply with court order to pay spouse support he pays when ever and how much he wants. I have attached hi

Sounds like you need a wage assignment.

If CPS agrees with my report, what will happen to my children? Will they be placed in foster care or into my care?

Call them and find out. Alternatively, you could petition family court based on your set of facts.