This may be a bit off topic as it more sits under the development side of things. As a full stack developer I can say that search functionality can be performance intensive. This all depends on what is searched, how much is searched, how much filtering is initially done, etc. I'd have the developers reevaluate the initial search functionality and see where it can be improved. There is generally always room for improvement.
This comment which probably came from the developers isn't accurate if things are being done correctly. "sorting feature causing problems in database and creating discrepancy in the data" This comment alone would make me weary of them. To me this is a cop-out for being lazy and not wanting to improve things.
I wouldn't remove the options if they are important to the page as their isn't much in way of search options to start. I see only 3 filters and this shouldn't be a significant performance hit.
It may also be that the placement of the filters is affecting their usage and changing this around may give different results. You may consider which filters are the most important for the user to obtain their goal and adjust as needed.