Economic growth can be measured by economic profit which is essentially the amount of transactions between individuals and corporations (speaking in terms irrelevant to GDP). The process of dollarization allows for a greater amount of the public to attain means to participate in these transactions. Therefore dollarization is very beneficial to economic growth.
No. Economic growth could be temporarily stimulated by the adoption of a neighboring country's currency, however this growth could not be sustained since the strength of that currency would be dependent on the economic growth of only one country. Also, both countries would be effected by an economic collapse of the other.