rear alignment screw

if the shop let you drive away with it then it must be O.K. While the rear wheels are used as a base line only the front has the adjustment and for the bolt to break is almost unheard of , may be take it somewhere for second opinion , or take a look yourself like you said "is it safe " ?

I'll look this morning when its light. I took a look at it while in the air and looked rusted together. Was not sure if it held more than just adjustment housing or if it keeps more together than it looks. Plan on getting it in shop asap but will be a few days before they can get to it. Thank you for your response.

not sure what you have but I would think the parts are available ,