Problem/Bug Bizarre side effect

Currently I am running a 1.10 Spigot server but a lot of my plugins are Bukkit/Craft Bukkit, here is the list

• MultiHome 0.40
• Multiverse-Core 2.5
• Multiverse-NetherPortals 2.5
• PermissionsBukkit 2.5
• PerWorldInventory 1.7.5
• Stargate 0.8.1
• WorldEdit "6.1.3;7a097ca"
• WorldGuard "6.1.2;e38d98d"

Despite the mostly way out of date plugins, this server runs beautifully aside from one minor flaw, End Portals. For a while End Portals just stop working. What I mean is, you would set it up, go through, get the sound effect and everything but you just fall right through into the lava underneath. In order to try to fix this problem, I deleted everything on my server and added it all back, step by slow step to where it was finally working again, End Portal and all, in every world.
Then as I was fighting the ender dragon, and died, when I ran back through the portal to get back, poof... same problem. I have found a work around this using other portals but it does ruin the ascetic of the End Portal.
I was wondering if anyone else had this issue or know if there are any more updates to the plugins I am using.
Thank you!