Double paired board - push the river or check behind?

[ClaytonN]

There was a lot of pause in his turn call. I really can't decide if he was on some kin of flush draw or strong draw, or if he has the case jack and a worse kicker.

***** Hand History for Game 3084864105 *****
$50 PL Omaha Hi/Lo - Wednesday, November 23, 21:41:53 EDT 2005
Table Table 64715 (Real Money)
Seat 6 is the button
Total number of players : 10
Seat 1: reeltimebw ( $34.40 )
Seat 2: RC276 ( $79.54 )
Seat 4: montey ( $61.20 )
Seat 5: LeeLoo444 ( $48.25 )
Seat 7: acting ( $63.31 )
Seat 10: PereCallahan ( $46.05 )
Seat 8: wilgs ( $47.60 )
Seat 6: Yeahman ( $49.80 )
Seat 3: LeeLay ( $49.50 )
Seat 9: siestapots ( $50 )
acting posts small blind [$0.25].
wilgs posts big blind [$0.50].
>You have options at Table 64978 (6 max) Table!.
siestapots posts big blind [$0.50].
** Dealing down cards **
Dealt to RC276 [ 4h Jd 4c Ad ]
siestapots checks.
PereCallahan folds.
reeltimebw calls [$0.50].
RC276 calls [$0.50].
LeeLay folds.
montey calls [$0.50].
>You have options at Table 68546 Table!.
LeeLoo444 folds.
Yeahman calls [$0.50].
acting folds.
>You have options at Table 66280 Table!.
wilgs checks.
** Dealing Flop ** [ Js, 8s, Jc ]
wilgs checks.
siestapots bets [$2].
>You have options at Table 68546 Table!.
reeltimebw calls [$2].
>You have options at Table 68546 Table!.
RC276 calls [$2].
montey folds.
Yeahman calls [$2].
wilgs folds.
** Dealing Turn ** [ 8d ]
siestapots checks.
reeltimebw bets [$4].
RC276 raises [$15].
Yeahman folds.
>You have options at Table 64978 (6 max) Table!.
>You have options at Table 64978 (6 max) Table!.
siestapots folds.
>You have options at Table 68546 Table!.
reeltimebw calls [$11].
** Dealing River ** [ 7s ]
reeltimebw checks.
RC276 _____________ ?