Okay for those that are interested in getting the dog tags, skins, and the peacemaker pistol, I have gone through the whole thing and with some help from the BFEE group have the knowledge and tools to help you.
BFEE and BF1 Wiki have really good guides that walk you through the process step by step. The hard part is decoding the morse code. The morse code is like the last latern in BF4; it's specific to the player. There are a couple that are the same but the guide points those out.
Now to decode the morse really easy, a guy from BFEE showed me an app that lets you see the code. The app is called audacity but you need a couple of plugins. I will post the links to the guides, the download link to the audacity, and the plugins. Those links are as follows:
http://bfee.co/index.php?title=Battlefield_1 BFEE guide
https://wiki.gamedetectives.net/index.php?title=Battlefield_1 BF1 wiki guide
https://www.fosshub.com/Audacity.html/audacity-win-2.2.2.exe audacity program
https://lame.buanzo.org/libmp3lame-win-3.99.3.zip first audacity plugin
https://lame.buanzo.org/Lame_v3.99.3_for_Windows.exe second audacity plugin
https://gyazo.com/1db9418ab59e97e396a3604adc142dac This link shows how to add the plugins to audacity.
Okay first part you have to record 9 different morse code messages on a given map (the original maps). Does not matter which map you listen to the code on. You have to find the headphones then go to the telagraph center. The guide shows the possible locations of the headphones and the telegraph on each map. You want to record (video) the morse code so you can input it into audacity. It has to mp3 or mp4 format. I used geforce experience to do mine.
Once you put it in audacity you change to spectogram format so you can see the code. If you have issues catch me on and I will show you how to do it. Then you put the code into an app created by BFEE to tell you were to go next. You will be directed to a particular map and one of three spots on that map. You have to find a symbol (very small) and look at it close up for four seconds. That allows you to go to the next step. Once you do all nine. You go to a particular map and spot and wait for a pigeon to fly by you. Dogtag one obtained.
The next part is really complex but if you follow the guide and use their spreadsheet you can get through it. It is similar to the latern puzzle in BF4. You can do it by yourself. It takes place on Soissons at the mansion. See the guide as it is too comlex for me to discuss here.
Third is a skin you will need for the final part. It takes place completely on Ablion. Follow the guide as it is probably the easiest of the five.
Fourth is the on Zeebrugge. It involves decoding a morse code using the infiltrator kit then inputing the code into the machines in building 1 and 3. Follow the guide and you should get through it with no problem.
The fifth part involves the cell room in Fort De Faux. Follow the guide listed in the link below and you will get the last dog tag you need. It does not tell you how to get the tag once you access the room. Give me a shout once you reach this and I will tell you the two things to do to get the dogtag.
http://bfee.co/index.php?title=Battlefield_1/House_of_Greg Cell room unlock
Finally after you have done all of the above you will have four dogtags and a skin for the LMG. YOU HAVE TO DO THE OTHER PARTS TO DO THIS PART OR IT WONT WORK. The guide for this part was just figured out and has not been published yet. I can walk you through it once you get to this part. It's not hard but too long to put in here.
I do have a server for a few more days (I think until Sunday) where you can go and do the steps. Just let me know and I will add you as an admin so you can restart or change maps as you need. If you get stuck just let me know and I will do what I can to help you. If you try this on a separate server IT HAS TO BE RANKED OR IT WILL NOT WORK.
"Do or do not there is no try!"