Is my van safe to make road trips?

I was driving down interstate and noticed when I accelerated to 60-65 mph, the front end of the van vibrated or rumbled, and when I accelerated it got worse, but when I de-celerated to 50mph, the rumbling went away. During this time my Check Engine Soon light came on, but went off when I slowed down.
Upon checking it out at the Service Center, the guys told be I had a broken motor mount and that was causing it to rumble with acceleration. They also said it was their belief that when the motor "rose up", it was stretching some sensor wires to make engine light come on.
They replaced the front right motor mount and told me that should take care of the problem with the shaking and engine light.
I started driving again on interstate and increased speed to 65mph, and the van didn't shake as bad as before, but it felt like it was still rumbling a little and I was afraid to go any faster.
Would this have caused my engine light to come on?
I travel for a living in a 150mile range, and I don't know if it's safe or not.
Should that have cleared up the problem? The engine light hasn't come back on since they fixed it.