not much more to add,other than that the phones nowadays are doing such complex checks,that downgrading the hboot is not possible without s off(or really nasty method of purposely bricking it in a certain way,so that you can "recover" it to an older hboot with a jtag-like method)
if you can find an OTA package,from someone else with your same firmware,it will contain a recovery image that you can use to flash back to stock if needed. hopefully you have made an unrooted nandroid as well for back to stock purposes,and move it somewhere safe on your PC,just in case
id be careful mix-n matching recoveries. different builds,and even different versions of the same build,typically have different md5s,so there are differences,however subtle they may be.