AnthonyLondon

By the way that website you quoted starts off factually incorrectly by saying DV2020 winners have to enter by the end of DV2020. Totally untrue.
and then of course the website shows its true colors by offering a 26% discount if you enter now!! Discount to what, one asks, when entering DV is free and the DV2020 entry period only opens (assuming DV still exists) in October? ...not exactly a website you want to trust.
 
here is the official stuff, read it well
https://www.uscis.gov/green-card/after-green-card-granted/international-travel-permanent-resident
https://www.uscis.gov/green-card/after-green-card-granted/maintaining-permanent-residence
 
In particular
Permanent residents are free to travel outside the United States, and temporary or brief travel usually does not affect your permanent resident status. If it is determined, however, that you did not intend to make the United States your permanent home, you will be found to have abandoned your permanent resident status.  A general guide used is whether you have been absent from the United States for more than a year. Abandonment may be found to occur in trips of less than a year where it is believed you did not intend to make the United States your permanent residence.  While brief trips abroad generally are not problematic, the officer may consider criteria such as whether your intention was to visit abroad only temporarily, whether you maintained U.S. family and community ties, maintained U.S employment, filed U.S. income taxes as a resident, or otherwise established your intention to return to the United States as your permanent home. Other factors that may be considered include whether you maintained a U.S. mailing address, kept U.S. bank accounts and a valid U.S. driver’s license, own property or run a business in the United States, or any other evidence that supports the temporary nature of your absence.
 

The embassy won’t be intereeted in you pleading your case; there are set procedures in place for approaching things. It’s not “in theory”, absent a reentry permit it is in fact. Unfortunately a reentry permit is really your only option at this stage. I can’t see a SB1 visa succeeding, professional reasons do not count as unavoidable reasons to return. You’d need to figure out if the hassles involved in getting a reentry permit are worth keeping your green card, or if you’ll sacrifice it. Unlike some other countries, a green card does not function as a super visa or give huge leeway: you’re expected to move to the US as soon as you can and establish residence properly. 
 
By by the way, did you file a 2017 tax return with the IRS?

"By by the way, did you file a 2017 tax return with the IRS?"
 
You never answered this

AnthonyLondon, Thank you for your information. My sister win the DV-2019, and she has plan to do same your case too. Please let us know too. It's very helpful.

In fact that's exactly what they say: 
 
https://egov.uscis.gov/coa/displayCOAInitForm.do
Change of Address
.....

If you are entering the United States on an immigrant visa, we will mail your Green Card to the mailing address in the U.S. you provided at the time of your immigrant visa interview or when you were admitted entry into the United States. If you move after you arrive in the U.S., please update your address.

The first quote is basically nonsense and playing with fire, ignoring that the concept of residence (required for maintaining a green card) goes well beyond touching down once a year - see the uscis pages on maintaining residence. The “if applied for” refers to a reentry permit.
You misinterpreted mine - and I specifically said more than 6 months, nowhere have I ever said more than a year at a time is fine. If you’d read the question I responded to, it was asking if a 7 month absence would be ok. A year is more than enough for most people to tie things up and again, if it isn’t for you, get a re-entry permit.