Assume you have a list like this:
XYZ    2    0    4    0    0    6    0    0    0    1
RST    1    0    0    0    0    4    3    0    0    1
MNO    4    7    0    0    0    0    0    4    0    2

Define this 3x11 array as MyArray.
Define another adjacent 3x11 array as MyAccu.
Insert > Name > Define > CSet and RSET respectively
=COLUMN(INDEX($1:$1,,1):INDEX($1:$1,,COLUMNS(MyArray)))
=ROW(INDEX($A:$A,1,):INDEX($A:$A,ROWS(MyArray),))
Tools > Options > Calculations > Iterate > 11 (your number of columns)
Select MyAccu and enter this array formula:
=IF(INDEX(MyArray,RSet,CSet-1)=0,INDEX(MyAccu,RSet,CSet-1)+1,0)
Adjacent, select a 3x1 column and enter this array formula:
=MAX(INDEX(MyAccu,RSet,))
The result should look like this:
0    0    0    1    0    1    2    0    1    2    3        3
0    0    0    1    2    3    4    0    0    1    2        4
0    0    0    0    1    2    3    4    5    0    1        5
You can hide MyAccu if desired.
The last column will show the maximum number
of adjacent 0's in a row in MyArray
Caveat: The last date is ignored to make things simple.

Try this where text in col a and numbers in col 2-11
Sub findlongestzeros()
For i = 1 To Cells(Rows.Count, "a").End(xlUp).Row
mc = 0
For j = 2 To 11
If Cells(i, j) = 0 And Cells(i, j + 1) = 0 Then mc = mc + 1
Next j
'MsgBox mc
If mc > mss Then
mss = mc
mr = i
End If
Next i
MsgBox "Max is Row " & mr
'MsgBox mss
End Sub