Yes, we can eliminate #2 and #3.

#1 is a total blank for me. The baptism 11 Nov 1810 St. George Douglas (John Gelling & Elinor Crellin) is perfect for date and place for matching to the census's, but not perfect for naming of children of Thomas and Agnes.

Children of John & Elinor, who married 13 Feb 1798 Braddan. They might have had more children than these four that I found on the IGI:
1. John 20 Nov 1803 St. George Douglas
2. Margaret 17 Mar 1805 St. George Douglas
3. Thomas 11 Nov 1810 St. George Douglas
4. Charlotte Elinor 1 Sep 1816 Marown.

There may be another Thomas that we haven't found yet, as Jean suggests. Meanwhile, maybe something more can be found about the folks above.