A quick Google search reveals the following recent paper: https://www.sciencedirect.com/science/article/pii/S2214914723000284 you may have some luck emailing the authors.
Note that this forum is generally staffed by people (volunteering!) who have experience using LAMMPS, but not necessarily using LAMMPS for polymer simulations (or any other specific topic, other than the ones we happen to do professional research in). As such, you will not be able to get a lot of specific information from us about how to simulate polymers.
However, if you have tried to perform some task XYZ that you expect to give results ABC but instead you are seeing results DEF, there is at least some chance that the specific issue will be one that some of us have seen before. Such queries are usually your best bet for getting help.
Also, being The Lone Computationalist is a difficult task and if you do not have sufficient local support, you are being set up for a very difficult time.