On what basis are Germany dominating the vote? They cannot. No EU member state can dominate a vote. Germany could at best lobby other member states, as other member states can (and do) lobby Germany.
The initial EU online public vote was dominated by German voters. There were 4.6 Million votes, of which 3 Million came from Germany [1]:
"More than 80 percent of respondents to the largest online survey in EU history are in favor of abolishing changing the clocks in summer and winter, EU sources reported Wednesday. Around 4.6 million people took part in the survey, which ran between July 4 and August 16. Three million of the respondents were from Germany.
And from the EU Commission report [2]:
"It should be noted that the largest amount of responses came from Germany (70% of all replies), which has a statistical influence on the average results."
That said, from section 3.2 of the EU Commission report, Cyprus & Greece were the only two countries where citizens voted to keep daylight saving.
[1] https://www.dw.com/en/eu-citizens-feel-times-up-for-changing...
[2] https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:52...
Anyway I leave my initial comment below.
I think you read that wrong. You should look at section 3.5.
"The highest share of respondents in favour of “permanent summertime” is in Portugal (79%), Cyprus (73%) and Poland (72%)."
"In the largest survey ever conducted by the European Commission, 80% of around 4.6 million respondents said they favor abolishing the finicky practice of changing the clocks in summer and winter"
"While citizens from all EU member states voted in the poll, around two-thirds of responses came from Germany "
https://qz.com/1375622/eu-citizens-voted-to-abolish-daylight...
AIUI in most other countries this initial pick-up and publicity just didn't happen.
In which languages?
Separately, the seats are divided into parties, and not all MEPs represent the interests of their national governments — UKIP prior to the referendum, for example.
Not quite, larger countries have fewer MEPs per capita[0][1]
[0] https://en.wikipedia.org/wiki/Apportionment_in_the_European_... [1] https://en.wikipedia.org/wiki/Degressive_proportionality
I suspect it comes down to the issue getting more publicity, interest and attention from media in Germany compared to other EU nations.