Actually, this is a question for KenoshaChris who is a U.S. attorney and he has just answered it below. I'll take the opportunity, however, to ask some questions, for a change:
A will under Dominican law can be drafted in three different ways: holographic, notarial or secret (?m?stico?). A holographic will must be entirely written and dated by hand by the testator. A notarial will must be written by hand by a public notary from the declarations given by the testator in the presence of at least two witnesses. A secret will is written by the testator or by another person at the request of the testator, signed by the testator, sealed and delivered to a notary public for safekeeping in the presence of six witnesses.
I would think that an expatriate can do a holographic will here in the Dominican Republic which will be accepted in the U.S. Please correct me if I am wrong.
As for notarial and secret wills as described above, would they be rejected by a U.S. Court just because they do not follow exactly the FORM established by the particular jurisdiction where it will be probated? Under Dominican law, there is a rule called "locus regit actum" whereby a Dominican judge looking at a foreign testament, will accept it as valid if it complies with the PROCEDURAL rules or FORMS considered legal in the jurisdiction where it was prepared. For this reason, wills prepared in the U.S. with the requirements you have stated below are accepted in the Dominican Republic even though they do not comply with Dominican law insofar as the form is concerned.