That link requires membership to view.
So you have a couple of possibilities for misinterpretation of his first name. He tells the German authorities his name when he departs - he has an accent - he may or may not speak German - they may or may not speak Lituanian - they write down what they think they hear - (you cannot presume that any clerks are familiar with any names) - the records are difficult to read - the indexers come along over 100 years later - they find the old writing difficult to read - German may not be the indexers first language - they make a best guess at what they see - German may be the indexers first language, perhaps a different dialect or they only know 'new' German - they don't recognize the name as being of German origin - they write what they think they see .... there are many different possible scenarios as to how they arrived at the name Marscha. This is also the same with his death record - there is plenty of opportunity for errors, misinformation and people just not knowing the man to give any details about him.
If this is definitely your ancestor how his name is written on one or two documents is irrelevant.
If you manage to find the Lithuanian record of his birth that may be different again. It is likely that he anglicised his name when he went to the USA, either intentionally or unintentionally (sometimes names people are known by, possibly easier to say, just stick, and they refer to themselves by this name as it is easier - hence being 'Moses' in the USA - he would never have to spell that).
We often see the one name written with different spellings in the same document written by the same person! So, a 'foreign' name in different countries on different documents written by different people and transcribed by different people is a prime candidate for variations. It would be nothing short of a miracle if is was the same on everything!
This also needs to be looked at in the context of the times - people were not so hung up on spellings as we are today, in fact some people would not have been able to spell, and it is very unlikely that they would have been asked how to spell their name.