Katie explained it very well in her answer. Let me add that in Hawaii, parties do not generally hire a real estate lawyer to go over contracts, unlike other states such as New York where I had the pleasure to practice real estate before moving to Hawaii.
Any reputable Escrow company in Hawaii will not let you open escrow without a "fully executed contract", meaning one that has been signed by all parties: sellers, buyers and both Brokerages.
Rosemary, I'm concerned about you - it sounds like maybe you're working with a Realtor who isn't explaining the buying process to you thoroughly or in a way that makes sense to you. Please feel free to call or email me directly, I'm happy to help sort things through for you. I do feel it's my duty as a Broker here in HI to make sure you are well represented and buying property can be one of the most stressful things to do in life, and can often be confusing, especially here in Hawaii. 808.895.4327 email@example.com.
When I was in Vegas I sent buyer's only signatures to escrow many times. With a good number of homes in Vegas being vacation homes, it was not uncommon for me to receive verbal accptance from a Seller that was out of state or the country. As my broker only used an escrow company and did not maintain his own escrow account, we had to turn in deposit money within 24 hours from notice of Sellers accptance. If it was going to take the seller a couple of days to get me his signature, I would send the paperwork over and they would assign escrow agent, numbers and start pulling prelims, etc.
It will depend on what the procedures of your escrow company if they will do this.
Is there just one buyer or multiple buyers?
By "go to escrow", do you mean open the escrow to start the process, or close the escrow taking title to the property?
What is the situation?