The datasheets for both ICs have a section called "output current." Both datasheets give the conditions for that output current:
That's 95mA into a 30ohm load when operated at 5V, with 2.5 V output.
Again, 95mA. But, into a 75ohm load operated on +- 5V.
You have to add in the quiescent current, of course. Also given in the datasheets.
It looks to me like your LTC1983 is a little on the weak side (100mA opposed to the 200mA both amps can draw,) at least if you are driving anywhere near the rated loads - and I expect you are, since both ICs are intended to drive video signals into typical video cable impedances.
You know your circuit better than we do. If you are driving lower loads, you might get away with just one LTC1983. If you are driving typical video signals, you'd do better with two LTC1983 (or a single converter that can supply more current.)