Hi,
Being a person who is 64 yrs old, now wearing dentures, I have in my lifetime, had every tooth in my mouth either filled, drilled, crowned, or extracted!
Been there...done that! I had gum disease at one point, didn't even know it, and the dentist I was going to, never mentioned it!
YES, it's normal to have a root canal before placing a crown on a tooth. I don't know why your dentist chose to do it that way. I am not a Dentist, nor a Doctor, nor a Professional in this area; just a man who has been through nearly all of it.
I would definitely go to another Dentist, and get another opinion. I won't guess at the reasons for the other Dentist, but another opinion will help you in deciding what to do. I am thoroughly familar with Insurance not paying for part, all, or whatever!
I do wish you the best, and good luck.
PS; I would recommend seeing a Family Dentist. He then can give you his/her opinion, what to do, and will refer you if needed; probably to a reputable dentist. Family Dentists are more likely to NOT be doing things not needed! At least, that's just my own personal observations over the years.