I have looked at a few definitions of remiss on line and was actually quite surprised to find that the Oxford Dictionary entry does contain examples of exactly this usage such as:
In this department it would be remiss to single out anyone, but one recalls one crunching tackle by Richard Berney on Cantan, when the full back came into the line with a touch down at his mercy.
And really, we don't know what happened, and I'd be remiss to even speculate about what did happen
I say I was surprised becasue I have always associated remiss with the words of and in giving (using other examples from the same entry):
It would be very remiss of me not to pass on that information
The council itself was remiss in not having had the building listed.
and neither of these has the form used in the quote. However it seems that it is a well-accepted usage. It is always possible, of course, that it is more common in US English than British which is my linguistic environment.