diff --git a/Data/ThunksDB.json b/Data/ThunksDB.json
index 277c37dce..6b2d862fb 100644
--- a/Data/ThunksDB.json
+++ b/Data/ThunksDB.json
@@ -54,7 +54,7 @@
       ]
     },
     "xcb-dri2": {
-      "Library": "libxcb_dri2-guest.so",
+      "Library": "libxcb-dri2-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-dri2.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-dri2.so.0",
@@ -62,7 +62,7 @@
       ]
     },
     "xcb-dri3": {
-      "Library": "libxcb_dri3-guest.so",
+      "Library": "libxcb-dri3-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-dri3.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-dri3.so.0",
@@ -70,7 +70,7 @@
       ]
     },
     "xcb-xfixes": {
-      "Library": "libxcb_xfixes-guest.so",
+      "Library": "libxcb-xfixes-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-xfixes.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-xfixes.so.0",
@@ -78,7 +78,7 @@
       ]
     },
     "xcb-shm": {
-      "Library": "libxcb_shm-guest.so",
+      "Library": "libxcb-shm-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-shm.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-shm.so.0",
@@ -86,7 +86,7 @@
       ]
     },
     "xcb-sync": {
-      "Library": "libxcb_sync-guest.so",
+      "Library": "libxcb-sync-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-sync.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-sync.so.1",
@@ -94,7 +94,7 @@
       ]
     },
     "xcb-randr": {
-      "Library": "libxcb_randr-guest.so",
+      "Library": "libxcb-randr-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-randr.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-randr.so.0",
@@ -102,7 +102,7 @@
       ]
     },
     "xcb-present": {
-      "Library": "libxcb_present-guest.so",
+      "Library": "libxcb-present-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-present.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-present.so.0",
@@ -110,7 +110,7 @@
       ]
     },
     "xcb-glx": {
-      "Library": "libxcb_glx-guest.so",
+      "Library": "libxcb-glx-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-glx.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxcb-glx.so.0",
@@ -118,7 +118,7 @@
       ]
     },
     "xshmfence": {
-      "Library": "libshmfence-guest.so",
+      "Library": "libxshmfence-guest.so",
       "Overlay": [
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxshmfence.so",
         "@PREFIX_LIB@/@PREFIX_ARCH@-linux-gnu/libxshmfence.so.1",
diff --git a/Source/Tests/LinuxSyscalls/FileManagement.cpp b/Source/Tests/LinuxSyscalls/FileManagement.cpp
index df4faf33a..1137da80e 100644
--- a/Source/Tests/LinuxSyscalls/FileManagement.cpp
+++ b/Source/Tests/LinuxSyscalls/FileManagement.cpp
@@ -317,11 +317,12 @@ FileManager::FileManager(FEXCore::Context::Context *ctx)
             (DBDepend->second.Enabled == false || AlreadyEnabled)) {
 
           auto ThunkPath = ThunkGuestPath / DBDepend->second.LibraryName;
-          if (std::filesystem::exists(ThunkPath)) {
-            for (const auto& Overlay : DBDepend->second.Overlays) {
-              // Direct full path in guest RootFS to our overlay file
-              ThunkOverlays.emplace(Overlay, ThunkPath);
-            }
+          if (!std::filesystem::exists(ThunkPath)) {
+              ERROR_AND_DIE_FMT("Requested thunking via guest library \"{}\" that does not exist", ThunkPath.string());
+          }
+          for (const auto& Overlay : DBDepend->second.Overlays) {
+            // Direct full path in guest RootFS to our overlay file
+            ThunkOverlays.emplace(Overlay, ThunkPath);
           }
 
           // Enabled, now walk this dependencies