If Dickert was a practicing gunsmith by 1770, there is little likelihood that he was trained by Albrecht--who arrived in Lititz in May/June 1771 (as Mart noted). At Lititz Albrecht did train William Henry, Jr. But WH Jr. was just 14, was formally apprenticed to Albrecht, and, as was usual in Moravian apprentice arrangements, came to live in the closed settlement of Lititz. I don't know of any situation--though there may be one--in any Moravian trade where an established tradesman (as Dickert was already an established gunsmith) received "training." (This is different than training an adult man who wishes to enter a new trade.)
In Nazareth, when William Henry (Jr.) had his own gun shop after 1780, the Moravian authorities carefully policed who he accepted as apprentices and indeed who he employed in his factories. There were careful records kept of all of this; whenever individuals came to or went from (or entered into some sort of business arrangement with) Moravian settlements, the overseer's committee had to weigh in and the committee's minutes recorded their decision. If Dickert had any formal relationship with Albrecht (which is unlikely given the timing), the Lititz Moravian records would register it.
This doesn't mean that the two men didn't influence one another in less formal ways. Rich's suggestion that Albrecht, upon arriving in Lancaster County, may have adopted Lancaster styles makes sense. The Lititz Overseer's Committee minutes do make it clear that Albrecht's trade was not flourishing:
19 June 1772:
Concerning Br. Albrecht's lack of work it was suggested: that he should have his work advertised. Then also that he should take a trip to visit a certain Lowry, who is an Indian trader and sells many guns, in order to introduce himself.