OP the issue is not the phone. It seems to me that you are looking for some sort of validation that your husband is wrong. It looks like there is very little trust in your relationship. Ask him straightforward and express your concerns. You are just going to hurt your mental health by letting your mind run uncontrollably in the wrong direction. Best to get straight answers and not draw conclusions.

To answer your question yes it’s possible to leave your iPhone at work and forward your calls to a different number. I hope you find peace