Okay, I've must have an lgc* directory somewhere.
I can't see it.

The question then is why does the script not return the same results as the single line commands?

#!/bin/bash -f
find /data/lgc*/basin_mas -name "1-S51*" -exec ls -lart {} \; 2>/dev/null >2.x
find /data/lgc*/basin_mas -name "1113-G6V*" -exec ls -lart {} \; 2>/dev/null >3.x
find /data/lgc*/basin_mas -name "1117-G6V*" -exec ls -lart {} \; 2>/dev/null >4.x
find /data/lgc*/basin_mas -name "1119-G6V*" -exec ls -lart {} \; 2>/dev/null >5.x
find /data/lgc*/basin_mas -name "1127-G6V*" -exec ls -lart {} \; 2>/dev/null >6.x
find /data/lgc*/basin_mas -name "12XW-AF5W*" -exec ls -lart {} \; 2>/dev/null >7.x
find /data/lgc*/basin_mas -name "14-UA8N*" -exec ls -lart {} \; 2>/dev/null >8.x
find /data/lgc*/basin_mas -name "150-F7U*" -exec ls -lart {} \; 2>/dev/null >9.x
find /data/lgc*/basin_mas -name "16X-AF5W*" -exec ls -lart {} \; 2>/dev/null >10.x
find /data/lgc*/basin_mas -name "2-V5*" -exec ls -lart {} \; 2>/dev/null >11.x

return this
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:43 2.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:43 3.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:43 4.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:44 5.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:44 7.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:44 6.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:44 9.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:44 8.x
-rw-rw-r-- 1 oneale expl 0 Feb 6 14:44 10.x
-rw-rw-r-- 1 oneale expl 348 Feb 6 14:44 11.x

with 11.x containing
-rw-rw-r-- 1 33682 expl 1296 Feb 19 2004 /data/lgc*/basin_mas/2-V5__________________________LEDUC_WABAMUN_iso______________________
_____________________.hzd_glb
-rw-rw-r-- 1 34124 expl 1296 Jan 15 2004 /data/lgc*/basin_mas/2-V5__________________________REG_WABAMUN_merge______________________
_____________________.hzd_glb

But when you run the command separately
find /data/lgc*/basin_mas -name "2-V5*" -exec ls -lart {} \; 2>/dev/null >11.z
you get
-rw-rw-r-- 1 oneale expl 2764 Feb 6 14:45 11.z
with 11.z containing.
-rw-rw-r-- 1 33682 expl 1296 Feb 19 2004 /data/lgc*/basin_mas/2-V5__________________________LEDUC_WABAMUN_iso______________________
_____________________.hzd_glb
-rw-rw-r-- 1 34124 expl 1296 Jan 15 2004 /data/lgc*/basin_mas/2-V5__________________________REG_WABAMUN_merge______________________
_____________________.hzd_glb
-rw-rw-r-- 1 33682 expl 1296 Feb 19 2004 /data/lgc10/basin_mas/2-V5__________________________LEDUC_WABAMUN_iso_____________________
______________________.hzd_glb
-rw-rw-r-- 1 34124 expl 1296 Jan 15 2004 /data/lgc10/basin_mas/2-V5__________________________REG_WABAMUN_merge_____________________
______________________.hzd_glb
-rw-rw-r-- 1 33682 expl 1296 Oct 20 2003 /data/lgc2/basin_mas/2-V5__________________________NISKU__________________________________
_____________________.hzd_glb
-rw-rw-r-- 1 33682 expl 1296 Oct 21 2003 /data/lgc2/basin_mas/2-V5__________________________NISKU_WABAMUN_isochron_________________
_____________________.hzd_glb
-rw-rw-r-- 1 jbutlin expl 924876 May 8 2002 /data/lgc3/basin_mas/2-V5__________________________cnc16000102.2v2_glb
-rw-rw-r-- 1 jbutlin expl 8044 Sep 30 2003 /data/lgc3/basin_mas/2-V5__________________________cnc16000101.2v2_glb
-rw-rw-r-- 1 33682 expl 1296 Oct 7 2003 /data/lgc8/basin_mas/2-V5__________________________WABAMUN_new____________________________
_____________________.hzd_glb
-rw-rw-r-- 1 33682 expl 1296 Oct 14 2003 /data/lgc8/basin_mas/2-V5__________________________LEDUC__________________________________
_____________________.hzd_glb
-rw-rw-r-- 1 33682 expl 1296 Oct 14 2003 /data/lgc8/basin_mas/2-V5__________________________WABAMUN_reg____________________________
_____________________.hzd_glb
-rw-rw-r-- 1 33682 expl 8044 Aug 25 2004 /data/lgc8/basin_mas/2-V5__________________________reg16tied01.2v2_glb
-rw-rw-r-- 1 33682 expl 924876 Oct 14 2003 /data/lgc8/basin_mas/2-V5__________________________reg16tied02.2v2_glb
-rw-rw-r-- 1 34124 expl 1296 May 4 2004 /data/lgc8/basin_mas/2-V5__________________________MH_Nordegg_____________________________
_____________________.hzd_glb
-rw-rw-r-- 1 34124 expl 1296 Jul 14 2003 /data/lgc8/basin_mas/2-V5__________________________MH_Wabamun_____________________________
_____________________.hzd_glb
-rw-rw-r-- 1 34124 expl 1296 Aug 28 2003 /data/lgc8/basin_mas/2-V5__________________________REG_WABAMUN____________________________
_____________________.hzd_glb
-rw-rw-r-- 1 33682 expl 1296 Oct 9 2003 /data/lgc9/basin_mas/2-V5__________________________WABAMUN________________________________
_____________________.hzd_glb