Is there any rational reason that he has not provided his version of the estimate to the home owners or to me as of yet?
No. I know you aren't in California, but here it is LAW that the estimate has to be provided to explain the settlement. It is just common sense really.
You are dealing with a staff adjuster from Allstate. He should have full authority - or be able to get authority directly from his manager. I am an Independent Adjuster. I work for lots of different Insurance companies, some are very full assignments where you negotiate an agreed repair figure with the insured or contractor, subject to the carrier's final approval.
Other carriers just want us to do an inspection and send them our estimate, without going over it with anyone else (less work for the adjuster, less pay, and the carrier can make any coverage or estimate changes they wish). If we do one of those, where we don't share the estimate with the Insured or his contractor, we put the following comment in our report:
[Please note that we have not sent a copy of our estimate to the insured. Section 2695.9 (d) of
the California Regulations requires the insurer to provide a copy of the estimate upon which
settlement is based to its insured. We can provide a copy to the insured if you so advise us.]
Here in California this particular law is only a few years old - but it has been my practice for over a decade in every state I have worked because it is just the right thing to do. State Farm requires a copy of the estimate go out with the settlement. If you have a fairly large loss - how else is the Insured going to know what is (or isn't) included in the scope of repair you are paying for? Explaining that stuff over the phone without having everyone reading the same sheet of music is maddening.
Even with a simple loss, you need a written estimate sent to the Insured. They can take it to a carpet store, explain that the insurance company is paying up to the closed doorway - but he wants to pay the difference to carpet the undamaged rooms. Same with roofing - what slopes are being considered. This is just a basic and standard action. What if depreciation is held back prior to completion of repair? That stuff has to be explained too - and you cannot do it without a line-item estimate. Are you 100% certain that the dollar amount "verbally" relayed to the Insured is the full Replacement Cost Value, and not the initial check at ACV? Do you know the starting point before deductible? All of that will be found on the estimate. When it gets complicated by advance payments, and supplements, it is spelled out on the Statement of Loss.
BTW, if the Insured is working with a contractor, and it is not one of those super-limited assignments, I will share my findings and negotiate an agreed figure directly with the contractor and inform the Insured as things progress. It makes no sense to try and cut the contractor out of the loop - the claim will never settle.