Knowing that there is a Catholic School in this episode and a rating that specifies sexual themes, these two might be related. I don't mean to offend anyone, but I'm sure most of us know what has been known to happen behind closed doors in Catholic religion institutes. The medical staff may be doing horrendous experiments for whatever purpose and documenting their findings or they could be making little more than snuff films of raping and mutilating girls or a combination of the two.
They might be trying to lure all survivors to their base of operations to continue the experiments and use the bell tower as a defense mechanism against anyone who might pose a threat to their plans or to simply get people to seek refuge in the school to be eventually taken hostage. The stack of bodies could be all their victims put there as a warning for all those who will try to fight against them. The radio guy might be trying to prevent this or is simply working with the villains to draw the group in.
There were rumors of these horrible things happening at the school prior to the outbreak, so this could fit in easily. Whatever the case, it's clear that these people were evil and twisted right from the start (not turned to evil by the zombie apocalypse like the other villains) and exploited the circumstances to continue their horrible endeavors. I think we may have found our main villains for the rest of the season.