Company buyout and no official compensation listed on offer . Help!

Company was bought out and tomorrow is first day of new employer. Prior to this we did background checks, filled out and I9 and participated in a town hall as well as weekly emails of FAQ’s. The new company said they can’t give us specifics until the sale goes through as we are still competitors . Although, multiple times we have been told our compensation would remain the same. (But jar town hall and in the weekly FAQ’s) Tomorrow is the first day with the new employer and we are to go into office with our drivers license and social security cards for HR. During the onboarding process we were told we were being offered the position of (fill in the blank), but there was no compensation amount in the paperwork. Fast forward to tonight, when I opened the last set of FAQ’s and it said compensation would remain the same for now, but that long term it may change to align with pay across the company. And if so, we would have plenty of advance notice. I don’t feel comfortable agreeing to work tomorrow when I have nothing in writing stating my pay. (This is a home health company, I am a therapist (PTA) but we also employ PT’s ,OT’s nursing, speech therapy and social workers ). Weirdly enough, I was unable to open when it was sent, but tonight I was able to open . Then the holiday weekend and sale is tomorrow. The whole thing is just not sitting right with me, and I worry that if I work tomorrow, without having an agreed upon pay rate, I have no guarantee of anything. It seems an employment lawyer may be necessary, but I don’t have the luxury of time. Has anyone experienced this or have any insight?