The second paragraph of your post is absolutely vital and I hope others responding pay attention to it.
At nearly 4, he already should have had a serious medical and psychological evaluation and should have been getting speech therapy or other therapy to find out why he does not speak at all except for poems and songs.
Have you had anyone evaluate his choice not to speak? At his age he should be talking up a storm. His pediatrician should LONG ago have referred you for professional help for what appears to be "selective mutism" -- search it online. He clearly CAN speak but chooses not to do so (if he can share songs and poems, the physical aspect of speech is present). A child in my daughter's class had selective mutism some years back and required a lot of intervention in order to get him functioning at school.
Do not rely only on preschool to "teach" him speak by exposure to other kids. You need to see professionals. It's not clear from the post whether maybe he already is getting help for the lack of speech and sending him to preschool is something you are doing on the advice of your doctors -- if so, that's great! If not, if you are sending him to preschool and he's not under any other therapy or evaluation, please, please get him seen. He is about a year and a bit away from kindergarten. He needs intervention now if he's not getting it. The preschool teachers are not therapists who are trained to focus just on your son and figure out why he refuses to speak.
Otherwise the second paragraph also tells a lot more and I think you already are aware that his being so unstructured and allowed to be "particular" has caused problems you are now reaping. He has been allowed to have what he likes, when he likes and even is allowed to tell you what dress to wear--? Did I read that right? Of course preschool is a shock to him; he's not the only child there and he has to do what he is told by adults who are not you or dad. He does need this experience because he cannot go until kindergarten just doing what he likes, having no structure in his day, and having to listen to no one but mom and dad -- that would be a recipe for a disastrous kindergarten year.
I'm hoping you'll update us that he's already getting help for the lack of speech and that preschool is something that a professional is backing here, and that the preschool teachers were well informed in advance about his issues (and the fact he has had no structure).
As for the crying and trying to escape: Pretty typical. Hard to believe he does it every single second, though--most kids get distracted by things going on at school and eventually stop this behavior after a few minutes. But even if he's upset the whole (short) time, he has only been going for one week. Do not let his crying etc. make you take him out now, or the message to him is that this behavior gets him what he wants -- and that's not a message he needs to get. Keep him there; give him structure at home so that he understands that this is the way things are there as well as at school; and stop letting him have what he wants, when he wants. Set limits, be willing to say "No" more if needed, and give him warning in advance of changes so nothing is ever a surprise to him -- but don't let his resistance make you cave in and let him go without any structure. Time to let home life match preschool (and very soon, kindergarten) life with more direction and structure.