The author of the EEPG plugin has always been very helpful. You should just contact him about adding Freeview HD support. Then you won't have to monkey around with patches and messing with the VDR core.
I think concensus is that the patch's code is cleaner than the plugin's. I looked at the plugin code to see if I could work out how to make the Huffman decoding work on standard PIDs for Freeview as well as on Freesat's non-standard ones, and found it too difficult to follow. The original author might not have so much difficulty, but there's also quite a big memory leak which somehow defied my efforts to trace it with valgrind.
I mentioned this thread to him yesterday. He gave a quick look but needs someone with access to Freeview HD to provide debug logs & test since he doesn't have that provider. Also, I've been using the latest git of EEPG for some time and haven't noticed any big memory leaks. When is the last time you've tried this plugin?
I used to have to patch the VDR core to get eit working here too. I must say, it's quite a pleasure to not have to maintain/fix it anymore now that I can just use EEPG. Even if you don't care about support for Freeview HD in EEPG, I don't see why you wouldn't just put your patch into a plugin and never have to hassle with fixing it again. I think most people prefer not to patch the VDR core at all when it can be avoided.