I just watched your video again, and I'm pretty sure that those are not alligator gar but are shortnose gars and/or longnose gars. The build of the gars seems to be much closer to that of a shortnose gar and/or longnose gar rather than an alligator gar. The fact that they appear to be shortnose gars and/or longnose gars would also explain for the relatively small size of the gars in that particular body of water as you mentioned in the video description since shortnose gars typically fall within the 20" to 28" range as adults in the wild and longnose gars typically fall within the 28" to 40" range as adults in the wild. Please remember that their pattern and coloration is completely useless for a positive ID in this case since they have greatly reduced patterns (if any) and coloration because of the clarity of the water that they were in.
Now then, on to screenshots of the actual gars in question.
For example, here's a screenshot of the one gar which appears to be a longnose gar:
View attachment 699036
These two screenshots appear to be of shortnose gars based on the build of the gars:
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