Why does this holding pattern have both minimum and maximum altitudes published?
So that it keeps you under the shelf of the adjoining bravo airspace and because the decent gradient may be steep enough to require an upper limit. As discussed here:

The instrument approach procedure Holding Pattern In Lieu Of Procedure
Turn (HILPT) is designed to facilitate alignment with the final
approach course. The descent gradient from the HILPT altitude to the
Final Approach Fix (FAF) altitude is limited by TERPS criteria to
permit aircraft deceleration and configuration for the final approach.
Due to a combination of this descent gradient requirement and the
surrounding terrain, it may be necessary to employ a smaller than
desired holding pattern template to define the HILPT protected
airspace. Use of this smaller template may require the designation of
a maximum holding altitude on the 8260-2 Form. This becomes the
maximum altitude the aircraft is permitted to enter the HILPT unless
ATC can ensure obstacle clearance by keeping the aircraft at or the
minimum vectoring altitude (MVA) or the minimum


(source)
(red circle is roughly where the hold is, arrow points to minimum altitude)