Can you take (2) 750mg methocarbamol at the same time?

Just remember this is a muscle relaxer, your heart is a muscle... don’t want to relax too much or you’ll never have pain again forever.

Yes what the first poster said. My family Doctor prescribed me 500mg three times a day lol. I told him that was way to low. I even showed him all the websites that state 6500mg loading does over a day for 3-4 days then 4000-4500 a day after. 1500 a day won't do anything for the majority of people

This from https://www.drugs.com/dosage/methocarbamol.html

"... Usual Adult Dose for Muscle Spasm

Oral:
Initial dose: 1500 mg four times a day for the first 48 to 72 hours, up to a maximum dosage of 8 g/day for severe symptoms.
Maintenance dose: 4000 to 4500 mg/day in divided doses."

Although you shouldn't up the dosage without your doctors permission it seems as though your doctor may have under dosed her (assuming she is a fit and healthy adult).
If pain is severe she could take 2 tablets 4 times a day for the first 2 to 3 days but no more than 10 a day.
You could call your doctor for clarification.